How might this question might best be analyzed?

A principal at a school has noticed some disturbing trends lately.There has been a large increase in vaping within kids in 6th, 7th, and 8th grade.He wants to investigate this further.He isn't sureif this is related to age, gender, home life, orhow pressured the kids feel from others?

Consider the following questions:

1.If a teacher were helping the principal investigate this further, what research question would work best? (Hint: there are a lot of possible questions, only focus on one)

2.Should they use a z-test, t-test, or ANOVA?How was this test chosen?

3.Briefly describe this study design making sure to include the comparison groups and hypotheses.