Seven elementary schools were as-
signed to one of three conditions. In the
specialist-led condition, certified physical
education specialists implemented the
programs. In the teacher-led condition,
classroom teachers were trained to imple-
ment the intervention because they are
responsible for teaching physical educa-
tion in most elementary schools.4 The
third condition was control, or usual
physical education, as implemented by
untrained classroom teachers.
Two consecutive cohorts of students
entered the study as fourth graders, and
students participated in their respective
experimental conditions in the fourth and
fifth grades. Self-report and fitness mea-
sures were collected near the beginning
and end of each school year.