Tax questions from the newby

Text message (edited) conversation with daughter who is about to do her own taxes for the first time.

Daughter: Will you claim me as a dependent?
Me: No, you're too old.
Daughter: Of yeah, I'm too old. Do I need to claim money that wasn't taxed? Like checks I get for lessons?
Me: You are supposed to, but most people do not report tips and other income that wasn't reported.
Daughter: I'll do my checks. But that means they'll take my money instead of giving me a break. :(
Me: No, it doesn't work that way. [I was at school and no longer at lunch at this point.]
Daughter: It doesn't? If taxes aren'e taken out, don't they take them?
Dad [suddenly joining the conversation]: You get a refund if you've overpaid your taxes.
Daughter: they don't take more? If you've underpaid?
[Photo of a yogurt container appears]
Daughter: BTW, this is good yogurt. No lactose.
Dad: If you follow instructions and do your taxes right, you will have had the correct amount deducted from your salary. In fact it is likely that you overpaid, so you may get a refund.
[Side note: Daughter is a young musician who doesn't have a full time job.]
Daughter: Ah, ok.
[Pause. Daughter is filling out tax form online]
Daughter: Man, my refund dropped a lot when I put in my teaching money. [sad face]
Me: Welcome to adulthood.
Daughter: [emoticon of crying face]
Daughter: OMG, I hate this. [More crying faces]
Daughter: Wahhh
Daughter: Oh no, I'm missing [one of her W-2 forms]
Dad: Call them. You have until April 15 to file.
Daughter: Ugh