ISLAPreventing School Exclusion and Opioid Misuse: Effectiveness of the Inclusive Skill-building Learning Approach (ISLA)

Teachers: The educator sample will include all educators within each of the schools. All educators that have regular contact with students (e.g., administrators, teachers, instructional assistants, school counselors) will participate in the school-wide ISLA intervention activities. All educators at both treatment and control schools, if they consent, will provide data through an annual survey administered at three time points: in the spring prior to the first year of ISLA implementation (baseline), in the spring of the first year of ISLA implementation (post-intervention), and in the spring of the second year of ISLA implementation (follow-up).

• Inclusion criteria:

\* Staff member in either a control or intervention condition school

• Exclusion criteria:

• None

Cohort Students: The student cohort sample will include all students in Grade 7 during the first year of ISLA implementation, who will be followed into Grade 8 during the second year of ISLA implementation (such that data can be collected from the end of Grade 6 to the end of Grade 8). With an average middle school size of 660 students per school, we project the cohort size to be 220 students per school, for a total of 11,880 to 13,200 students.

Sub-cohort Students: A random sample of 50 assenting 6th grade students (at the time of baseline data collection) per cohort per school will be selected to provide additional data, for a total of 2,700 to 3,000 students (consent will be gathered from parents/guardians). With the help of each school administrator, the research team will conduct the randomization process using each school's enrollment. School administrators will invite all 6th grade students to participate via recruitment emails to their parents/guardians. A random selection of students will be made from those parents who are consented.

• Inclusion Criteria:

\* 6th grade students in either intervention or control schools during first data collection period for each wave

• Exclusion Criteria:

• students who cannot complete the online survey independently (e.g., require assistance beyond text-to-speech files to comprehend the items and available responses) specifically:
• students who cannot comprehend written or spoken English or written or spoken Spanish, or
• students who are eligible for alternate assessment for statewide achievement testing.