Trial Outcomes & Findings for Developing Inclusive Youth: Promoting Intergroup Friendships and Inclusive Classrooms in Childhood (NCT NCT05619523)

Results Overview

The School Belonging Scale is an 8-item self-report measure consisting of a rating scale ranging from 1 (really not true) to 6 (really true). The average of all items creates a final score of perceived school belonging in which higher scores indicate higher levels of perceived school belonging. The original Psychological Sense of School Membership scale (PSSM) (Goodenow, 1999) measure has been found to have internal consistency reliability for both suburban (0.875) and urban (0.803) elementary school populations. We modified this measure for length. Pilot testing revealed that this new, shorter version was also found to have high internal reliability (0.714). The construct validity of the scale was also indicated through a significant relationship with teacher-ratings of student social standing (Goodenow, 1993).

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

885 participants

Primary outcome timeframe

one week following completion of the 8-week intervention

Results posted on

2025-09-02

Participant Flow

We recruited elementary schools in the local public school district by sending an email invitation to every school in the district. Once the schools elected to participate, families received hard copy or electronic consent forms in English, Spanish, and/or Mandarin. Students who returned consent forms received an eraser. Participating schools received $1500 and teachers with students in the intervention group received $150 to compensate for their time administering the program.

Teachers were potential participants who were screened for the purpose of determining eligibility, but who did not participate and thus were not considered enrolled, due to the low frequency of potential participants (N = 51). Teachers whose students were in the intervention group were compensated for giving up instructional time to the intervention and for helping facilitate delivery of the program.

Participant milestones

Participant milestones
Measure	Intervention: DIY Tool Classrooms Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Overall Study STARTED	522	363
Overall Study COMPLETED	522	363
Overall Study NOT COMPLETED	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Developing Inclusive Youth: Promoting Intergroup Friendships and Inclusive Classrooms in Childhood

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.	Total n=885 Participants Total of all reporting groups
Age, Categorical <=18 years	522 Participants n=5 Participants	363 Participants n=7 Participants	885 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Categorical >=65 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Continuous	9.67 years STANDARD_DEVIATION .95 • n=5 Participants	9.72 years STANDARD_DEVIATION 1.01 • n=7 Participants	9.69 years STANDARD_DEVIATION .98 • n=5 Participants
Sex: Female, Male Female	251 Participants n=5 Participants	180 Participants n=7 Participants	431 Participants n=5 Participants
Sex: Female, Male Male	271 Participants n=5 Participants	183 Participants n=7 Participants	454 Participants n=5 Participants
Race/Ethnicity, Customized Asian	74 Participants n=5 Participants	59 Participants n=7 Participants	133 Participants n=5 Participants
Race/Ethnicity, Customized Black	62 Participants n=5 Participants	42 Participants n=7 Participants	104 Participants n=5 Participants
Race/Ethnicity, Customized Latine	74 Participants n=5 Participants	45 Participants n=7 Participants	119 Participants n=5 Participants
Race/Ethnicity, Customized Multiracial	68 Participants n=5 Participants	59 Participants n=7 Participants	127 Participants n=5 Participants
Race/Ethnicity, Customized White	191 Participants n=5 Participants	122 Participants n=7 Participants	313 Participants n=5 Participants
Race/Ethnicity, Customized Other/Unknown	53 Participants n=5 Participants	36 Participants n=7 Participants	89 Participants n=5 Participants
Region of Enrollment United States	522 participants n=5 Participants	363 participants n=7 Participants	885 participants n=5 Participants

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

The School Belonging Scale is an 8-item self-report measure consisting of a rating scale ranging from 1 (really not true) to 6 (really true). The average of all items creates a final score of perceived school belonging in which higher scores indicate higher levels of perceived school belonging. The original Psychological Sense of School Membership scale (PSSM) (Goodenow, 1999) measure has been found to have internal consistency reliability for both suburban (0.875) and urban (0.803) elementary school populations. We modified this measure for length. Pilot testing revealed that this new, shorter version was also found to have high internal reliability (0.714). The construct validity of the scale was also indicated through a significant relationship with teacher-ratings of student social standing (Goodenow, 1993).

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
School Belonging Scale	4.72 score on a scale Standard Error .07	4.72 score on a scale Standard Error .09

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

This is a five-item measure including items about whether other students in my class care about me and other students in my class like me for who I am. The measure has been found to produce reliability figures of .92 (Van Ryzin, Gravely, \& Roseth, 2009) and our modified version utilizing a 6-point response scale in place of the original 5-point scale found similar reliability scores (0.896). The rating scale ranged from 1 (really not true) to 6 (really true). The average of all items creates a score of perceived peer personal support in which higher scores indicate higher levels of perceived peer support. Performance on the Van Ryzin et al. (2009) scale has been demonstrated to have an independent positive effect on engagement in learning and has been validated by connections to academic engagement (Collie, Martin, Papworth, and Gins, 2016).

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Classroom Life Scale: Peer Personal Support Subscale Personal Support Subscale	4.35 score on a scale Standard Error .08	4.40 score on a scale Standard Error .11

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

The degree to which students perceive their teachers as personally supportive will be assessed using this 4-item measure. Items include statements such as my teacher cares about me and my teacher likes me for who I am. This measure was also modified from the original rating scale to a 6-point rating scale, which ranged from 1 (really not true) to 6 (really true). Van Ryzin et al. (2009) reported an internal consistency reliability of .91, and our pilot testing found a similar internal consistency reliability, 0.893. A composite score was computed using the mean of all items in the scale. Scores ranged from a minimum of 1 to a maximum of 6. A higher score indicated higher teacher support, the more desirable outcome.

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Classroom Life Scale: Teacher Personal Support Subscale	5.12 score on a scale Standard Error .06	5.03 score on a scale Standard Error .09

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

An adaptation of the Child Occupations and Traits (COAT) scale (Liben \& Bigler, 2002; 0.99) measures stereotypes re: gender and race intergroup categories. Participants respond to three types of items (e.g., how smart or not smart; how hardworking or lazy; or friendly or mean) and this measure was also modified to utilize a 6 point rating scale. There are two sub-categories, gender and race. The questions probe the degree to which children assign traits to specific groups. The version we utilized contained 12 items, 6 about race and 6 about gender and pilot testing revealed that this version had a high internal reliability for the full scale (0.919), as well as for the gender and the race subcomponents (0.859 and 0.849, respectively). Scores ranged from a minimum of 1 to a maximum of 6. A higher score indicates more positive (better) trait attributions about peers.

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=502 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=343 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Trait Attributions for Gender, Race, & Ethnicity	4.83 score on a scale Interval 4.45 to 5.36	4.82 score on a scale Interval 4.39 to 5.25

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

This set of items is adapted from Liben \& Bigler (2002). These items probe participant perceptions of the likelihood of group members obtaining high status occupations. Participants were asked "Which kid do you think will grow up to be a \[pilot/doctor/lawyer/scientist\]?" with one item for each profession. Participants selected which child of 8 possible choices they thought would become the profession. The 8 choices included a boy and a girl of each of the following racial groups: Asian, Black, Latine, White. The measure was made binary by whether participants selected an underrepresented minority (URM) (Black or Latine) in high status professions, or whether they selected a race group that is not underrepresented (White or Asian). The goal of the intervention was that more students in the treatment condition selected a URM student after the intervention program. Therefore in the fields below, the category Underrepresented Minority (URM) indicates the number of participants who select

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=499 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=342 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
High Status Occupation Expectations Doctor · Underrepresented Minority (URM)	204 Participants	131 Participants
High Status Occupation Expectations Doctor · Highly represented group (non-URM)	295 Participants	211 Participants
High Status Occupation Expectations Lawyer · Underrepresented Minority (URM)	269 Participants	185 Participants
High Status Occupation Expectations Lawyer · Highly represented group (non-URM)	230 Participants	157 Participants
High Status Occupation Expectations Pilot · Underrepresented Minority (URM)	215 Participants	143 Participants
High Status Occupation Expectations Pilot · Highly represented group (non-URM)	284 Participants	199 Participants
High Status Occupation Expectations Scientist · Underrepresented Minority (URM)	185 Participants	138 Participants
High Status Occupation Expectations Scientist · Highly represented group (non-URM)	314 Participants	204 Participants

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

The diversity of friendships will be assessed using an adaptation of the Friendship Questionnaire (Bierman \& McCauley, 1987). The original measure has been widely utilized to assess the quality and quantity of children's peer interactions and has proven to be reliable (ranges from .72 to .82). The adaptation consisted of adding the intergroup categories of gender and race/ethnicity. This adapted version was also found to be internally reliable (0.659). Using gender, racial, and ethnic background, we will record how often they play with outgroup peers to determine the proportion of cross-gender, cross-race, and cross-ethnic playmate interactions. Scores on the scale ranged from a minimum of 1 to a maximum of 6. Higher scores indicate a higher level of reported cross-group contact, which is the more desirable outcome.

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Reported Contact Scale	3.34 score on a scale Interval 3.0 to 3.67	3.31 score on a scale Interval 3.0 to 3.67

PRIMARY outcome

Timeframe: change, one week following completion of the 8-week intervention

This assessment consists of 5 separate items about how much the child wants to play with X, where X refers to pictures of girls, boys, and kids who are depicted as African American, European American, and Asian American). Response choices are provided on a 6 point rating scale ranging from 1 (really do not want to) to 6 (really want to). During pilot testing this measure was found to have a high internal consistency reliability (0.767). Using students' gender, ethnic, and racial background, we will record their desire to play with outgroup peers to determine the proportion of cross-gender, cross-race and cross-ethnic playmate preferences. Scores on the scale ranged from a minimum of 1 to a maximum of 6. Higher scores indicate a higher desire for intergroup contact, the more desirable outcome.

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=343 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Desire for Intergroup Contact	3.99 score on a scale Interval 3.33 to 4.67	3.92 score on a scale Interval 3.17 to 4.58

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

This assessments consists of 8 items about whether the child experiences exclusion in a school context. Response choices are provided on a 5 point Likert-type rating scale ranging from "Never" to "Always." This measure has been validated in previous research (Killen et al., 2022). Scores on the scale range from a minimum score of 1 and maximum score of 5. Higher scores indicate higher levels of personal experiences of exclusion, which is the less desirable outcome. Thus the goal of the intervention is to result in lower scores in the treatment group at posttest.

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Personal Experiences With Exclusion	2.02 score on a scale Standard Error .06	1.96 score on a scale Standard Error .08

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

This assessment consists of 2 items repeated 4 times to reflect different race and gender combinations for a total of 8 items. This measure is adapted from Cooley et al., 2019. The items ask participants to evaluate exclusion in an intergroup and same group social context. Responses were on a 6-point Likert-type scale ranging from 1 (really not okay) to 6 (really okay). Scores on this scale range from a minimum of 1 to a maximum of 6. A higher score on this scale indicates viewing exclusion as more acceptable and a lower score indicates viewing exclusion as less acceptable. The goal of the intervention is to promote lower scores, indicating participants are less accepting of exclusion.

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Evaluations of Exclusion in Intergroup and Same Group Contexts	3.05 score on a scale Standard Error .07	2.96 score on a scale Standard Error .09

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

This assessment consists of 5 items repeated 4 times to reflect different race and gender combinations for a total of 20 items. This measure is adapted from Cooley et al., 2019. The items ask participants to predict the likelihood of a child inviting someone to their birthday party, where the children they can invite may be of the same or a different race. Responses were on a 6-point Likert-type scale ranging from 1 (very unlikely) to 6 (very likely). Scores on this scale range from a minimum of 1 to a maximum of 6. Higher scores indicate participants expect intergroup inclusion to be more likely, which is the more desirable outcome.

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Likelihood of Inclusion in Intergroup and Same Group Contexts	4.53 score on a scale Standard Error .05	4.54 score on a scale Standard Error .06

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

This scale is adapted from Liben and Bigler (2002). The scale probes participant perceptions of the inclusivity levels of different groups. These scales were created consistent with the literature on gender stereotypes (Berenbaum, Martin, \& Ruble, 2015; Mulvey, Rizzo, \& Killen, 2016). A 5 point rating scale ranging from 1 (none) to 5 (all) indicates the proportion of children within a hypothetical target group whom participants believe fit into a categorization. Pilot testing revealed 0.800 for the 5-item measure of inclusivity levels of different groups. Scores on this scale range from a minimum of 1 to a maximum of 5. Higher scores indicate more positive beliefs about peers' inclusive behavior, the more desirable outcome.

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Stereotypes About Inclusivity	3.70 score on a scale Interval 3.17 to 4.08	3.75 score on a scale Interval 3.17 to 4.17

PRIMARY outcome

Timeframe: one week following completion of the 8-week intervention

This scale is adapted from Liben and Bigler (2002). The scale probes participant perceptions of the math and science abilities of different groups. This scale was created consistent with the literature on gender stereotypes (Berenbaum, Martin, \& Ruble, 2015; Mulvey, Rizzo, \& Killen, 2016). A 5 point rating scale ranging from 1 (none) to 5 (all) indicates the proportion of children within a hypothetical target group whom participants believe fit into a categorization. Pilot testing revealed 0.796 for the 5-item measure of math and science abilities of different groups. Scores ranged from a minimum of 1 and a maximum of 5. Higher scores indicate more positive beliefs about peers' math and science abilities, which is the more desirable outcome.

Outcome measures

Outcome measures
Measure	Intervention: DIY Tool Classrooms n=522 Participants Developing Inclusive Youth (DIY) classrooms complete a pretest and posttest survey in addition to completing 8 scenarios using the DIY online tool and a class discussion for each scenario. Developing Inclusive Youth (DIY): Developing Inclusive Youth (DIY) is a web-based curriculum tool that serves as the intervention program. The animated and narrated tool displays eight peer social exclusion scenarios in a range of familiar everyday social contexts (such as the playground and school). Children enter their responses while watching the scenarios. Responses include making decisions about inclusion and exclusion, evaluating the actions as okay or not okay, attributing feelings to includers, excluders, and excluded characters, and selecting reasons that best match their justification for their decisions and evaluations. The program includes teacher-guided group discussions following use of the tool in which teachers facilitate discussions about children's interpretations of the scenarios, evaluations, reflections regarding their own experiences of exclusion, and solutions. Participants will view and discuss 8 scenarios and engage in a discussion for each one over the course of 8 weeks.	Control: Business As Usual Classrooms n=363 Participants The control group follows a Business-As-Usual plan (no "alternative" program is implemented for the control group.) They complete a pretest and posttest in the same weeks as the experimental group.
Stereotypes About Math & Science Competence	4.89 score on a scale Interval 4.58 to 5.39	4.89 score on a scale Interval 4.5 to 5.25

Adverse Events

Intervention: DIY Tool Classrooms

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Control: Business As Usual Classrooms

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Melanie Killen

University of Maryland, College Park

Phone: (301) 405-3176

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place