Hi,
That definitely sounds like a very doable and productive project. There are several ways to do this, depending on how detailed you want to get about it.
At the most basic levels, you can pick simple enzymes, combine them with their substrates, and depending on the enzyme, you can measure how fast product is being formed. A good few examples for this would include amylase (starch --> glucose, this is detectable in the presence of iodine, see the iodine test here:
http://en.wikipedia.org/wiki/Iodine_test), peroxidase (common in ELISA tests for detecting antibodies, it breaks down a substrate visibly, see more about ELISA and its biomedical research use here:
http://en.wikipedia.org/wiki/ELISA), peroxidase (can also be used more simply to break down hydrogen peroxide, this happens in peroxisomes in human cells), etc (the possibilities are quite endless, even most common objects rely on enzymes, and these reactions can be measurable,
http://en.wikipedia.org/wiki/Enzymes#Bi ... l_function).
So, in quick review, consider what enzymes you think you can get, and what you find interesting. A lot of the enzyme/substrate reactions produce visible color (amylase, peroxidase above, and more) or other measurable changes.
Cheers! Hope this helps,
Aaron Lin