I need Help!!!!!!

I need to find a xmas present for my roomate jim....He is a perpetual 10 year old who loves novel things..ive found a bunch of stuff, but nothing has really caught my eye...the other problem...money is so tight that i can only spend about $15....so if any of you have any suggestions or sites you can direct me to i would be forever thankful...thank you in advance
He likes:
Science
Bonsai
Fart jokes
and other novel stuff

you have a 10 year old room mate??:O! i want one too
Sorry i cant suggest anything coz the things he likes i dont like maybe the fart jokes though

Somebody did mention Bonsai though on the site maybe they can help you?

well hes 23 lol......but he acts 10...i think i was the one who mentioned Bonsai...lol....but thank you anyways

One thing that I can think of that I get my 23 year old going on 10 fiance is, at books stores you can find all the little books and boxes that are all just pointless little things.. There are all different kits, and books (one I got was The Dummie's Guide to Bartending)
I think they are about $9 CDN so you could probably buy more than one