Hairspray the lens if you wish to lose the video function and render the camera useless without thorough cleaning. If you ever need to outsmart them there are electronic jammers available online. If you're low on cash like I was in my teen years, then you could do any job opportunities to raise your financial status, find blueprints for such a device and just order the parts and assemble it yourself.

Now when it comes to abusive parents, just do you're absolute best to stay at school, finishing all the study programs you can and absorb as much information as possible. LISTEN to your own heart in order to find out what you'd absolutely love to do. There's this really great buddhist proverb, that if you do what you love for living, then you'll spend your life without working a single day.

I grew up in a heavily abusive environment and trust me, narcissistic egomaniacs, psychopaths or people in general who may suffer under severe mental imbalances do not always wish to change for the better.
So what can YOU do about it? Live your life still to the fullest, try to get along with them but do not sacrifice your own mentality and/or physical health in the attempts of saving someone else. It just simply is not possible to the extent we'd wish it to be. When trying to change anyone else, first think how difficult it may be to change ourselves at first.

The sooner you can start earning your own income the better. Even if it is on a low scale at first, no worries. Everyone has to start from somewhere. Plus going to work is awesome excuse to get out from a abusive environment without them being able to say anything about it, unless your grades start dropping or something like this.
Try to physically exercise at least three times a week, very good for body and mind overall. And if you should fall a victim to domestic violence then REPORT it As soon as possible! That does not mean you would hate them or anything like that, quite the contrary. By sometimes forcing people to get help with THEIR own inner baggages we end up doing them a huge favour. Don't EVER believe that you're not good enough, pretty as a person or something like this. Focus on positive outcomes, do not worry about HOW you're going to get there- universe will figure out the how part for you. So long as you follow one course until success, all great. Meditate, spend time in nature during weekends for example. Do not decay away quietly indoors, that is bad for mentality (speaking from personal experience). Socialise with others, make new healthy connections. People who see you trying will eventually step in to assist with whatever they can, so long as you're hungry for success. Set goals, make yourself a vision board to help you map out some ideas what you may love the most.

Keep trying, keep going, do not stop especially when it gets hard, that only means that something great is about to come your way! Fall down seven times, but stand up eight.