Heh! I'm a science fair mentor I'm so pleased that you're so keen to make a good impression.
I agree - new fibers is a good place to start. There are all sorts of new things coming out - soy fibers, banana silk and that new SeaCell stuff (check out Handmaiden SeaSilk - it's supposed to have all sorts of medicinal qualities).
One of the big things in science is the use of biological products for engineering (eg: biofilm adhesives made from marine organisms, etc) so if you're looking at other non-hair alternatives it will be catchy. Maybe you could look at tencil strengths or measure how quickly they degrade compared to tradional materials (silk, wool, hair, cotton etc)
Also, you could look at novel dying processes. What is cutting edge and how do traditional dying methods match up with these new bio-fibers? Maybe do some dying experimentation with traditional dyes and new ones?
Just some ideas... if i think of any others, i'll let you know..
- (dr.) hh