I don't know how to parent a teenager, it seems 
Dd 13 is not very motivated. Her interests are YouTube videos, face timing with her friends, playing SIMS, stuff like that. She isn't interested in doing homework and seems to do the bare minimum at the last moment, just to get it done.
At this age I thought she should be taking responsibility for her work herself, that I shouldn't have to nag and remind her all the time.
She has turned out very spoilt, does no chores unless reminded, and then she glowers and stamps. And that's just when I ask her to take the plates into the kitchen and put them in the dishwasher.
Yesterday we went to parents evening, all her teachers said get work was good, although she seems to daydream and not finish her work, that she needs to be going back over past homework and doing the "EBI" (even better if) and also doing some french practice and reading some challenging books.
She used to read lots, but these days only reads trashy books if at all. Her Kindle is full of all sorts including classics, but she's not interested.
When she gets in from school I'm usually working and is not work that I can do at another time, there is a short turnaround time for all my work. So I can't sit with her to make sure she does enough work. Most days she comes home, I ask if she has homework, she says she doesn't know and that she will check, then she goes to the loo, gets something to eat .. In the meantime I've carried on with my work. Then after dinner I'll ask her if she's done her homework and she still hasn't checked!
She is always miles away, these days usually due to her phone and the texts etc she's receiving, but she has always been a daydreamer.
She has already started her gcses as her school is taking three years for them. She doesn't seem mature enough to take responsibility for the work required.
Any thoughts?