Your tax bracket likely doesn’t matter because ‘then some’ is unearned income taxed at your parents’ marginal rate.
I had to file separately this past year, so as far as I know it’s not taxed at my parents’ rate. Or, at least, FY14 wasn’t.
Unearned income is taxed on your tax return but potentially at your parents’ rate. See Form 8615.
Ah, great.