15
16
activity
adolescents
austrian
boys
caucasian
class
classmates
collaborating
college
divided
educational
enjoying
european
exercise
females
friends
german
girls
group
hand
helping
indoors
information
interest
lesson
males
method
project
pupils
raise
school
skill
split
students
studying
swede
talking
task
technique
teenagers
time
training
university
working
young