Dd aged 14 is not showing a lot of interest in school work, home work, reading ..
We've had a difficult time, I separated from her father, we moved house, new school. However, the lack of interest predates all of that. Really it's been like this since she started high school. All she wants to do is talk to her friends, be on YouTube ..
I don't want to see her do badly in her gcses.
Can I ask how others handle this? Do you leave them to it or stand over them, making sure they do revision for two hours a night?
If I left her to it, she would spend all her time on her laptop in her room. I do understand, I remember what it's like to be a teenager, but would like her to interact with me a little bit.
She's very sensitive and has a bit of history of self harming, so I can't just wade in, I'll have to stay calm and encouraging 
We're also having a bit of a disagreement about her mobile. I want her to leave it downstairs at night, she says it's the only alarm that wakes her up! I'm sure she spends all night messaging and skyping. She struggles to get to sleep at a reasonable time anyway.
Any advice on how to handle these issues without starting a battle? I don't really have anyone I can talk to about it. Her dad was a waste of space and I feel things have got out of hand and I'd like to turn them around before it's too late.