http://mysite.verizon.net/georgeandjoni/archer.htmlDefinitely check out Jawge's site. In fact, have your parents check it out. Better yet, have them check out some of the posts on this site. Sell it as a project you can all do together. I know that is a heavy burden, having to hang with the 'rents, but tough it out and you might end up with a bow out of the deal!
A red oak 1x2 will run you about $8. Not sure what you will have around the house for tools, pawnshops and flea markets and junk stores are a great bet! String making material will be a bigger cost outlay, but play nice and someone here might make you a string *wink*.
You have your assignment. Get to work!
....and as always, post pics of your project as it goes along.