Does you school offer Arts Awards? They are great way to get credits for some of the creative things that you already do - and you get an award and a certificate!
There are different awards that you can work towards starting with Discover - perfect for younger children running through Bronze, Silver and finally Gold. A Gold Arts Award actually has 35 UCAS points attached for young people looking to go to University!
Do ask your teacher about Arts Awards and you could start getting qualifications for the creative things you already do!