Hi hebert,
I can recommend you check out the website
http://www.stumptuous.com/weights.html
This has a lot of stuff about weights training, inclus=ding one about how to use household items (cans of soup ? ) as weights. Also there is some info about do's and dont's for younger people. As 16 year old, I think you should be carefull in lifting because you presumabely are not fully grown yet.
rabbit