Table 3.

School eligibility criteria

1	The student body is representative of the adolescent population at risk for type 2 diabetes, defined as either at least 50% minority (African American, Hispanic/Latino and/or American Indian) and/or greater than 50% eligible for free or reduced lunch.
2	Annual student attrition from all causes is ≤25%.
3	Expected cohort size at end of study is at least 50 per school.
4	School authorities are willing to accept randomization of an individual school to intervention or control. If a school is assigned to the intervention program, this means that the school must arrange for the following if needed: Students attend PE class for a minimum of 225 min every 10 days over the course of the intervention. PE class attendance is mandatory and continuous for the cohort, that is, sixth, seventh and eighth graders in the intervention school years (with school specified medical exceptions in individual cases). The school has at least one play area that satisfies intervention requirements as determined by the field center staff.
5	School authorities permit grade-wide collection of height, weight, gender, age and race/ethnicity at baseline.
6	The school assists with mass mailings of study materials to students’ homes.
7	The school district possesses or obtains Federal Wide Assurance (FWA) to conduct research.
8	Appropriate school authorities agree to adhere to the protocol.