Education

Ok. I have a son who is a college senior ready to start his last semester. He also has a full scholarship and therefore has not touched his 529 money. I therefore want to withdraw from the 529 to be disbursed to him to the extent that his $20K scholarship for this semester allows. As this is unearned income I think I should no longer claim him as a dependent. Is that correct? I believe the unearned income may come back to me if I claim him as a dependent. He has a job when he graduates in May and will be working 7 months this year and should be in 12% marginal tax rate.