1417
2935
activity
adolescents
adult
african
attention
black
boys
caucasian
class
college
complicated
credit
curiosity
desks
difficult
european
examination
explaining
females
girls
indoors
information
interest
lecture
lesson
listening
males
man
multiethnic
problem
professor
pupils
question
questioning
revision
school
students
task
teacher
teenagers
test
university
white
writing
young
youth