I really would like to be able to sing?

I am 14, male, and I can sing a bit. I can do some of the basics but my voice seems to lack... well I don't know, it just doesn't sound very musical. Is there any way to "train" your voice or any other tips that could help me acquire a nice singing voice? I used to get lessons a few years ago but dropped out due to other things prioritising over it. My teacher seemed to think I was pretty good, but I really want to try it again. I don't want lessons again though. I am aware that my voice is pretty low in pitch at the moment, any ideas when I will be able to sing a bit higher? :P I like to sing many types of music. My favourite artists being Coldplay, One Republic, Green Day and James Morrison. Any ideas what I can do? Thanks in advance.