We don't have science fairs around here, so I'm not sure of your terminology or what you need, sorry.
Can you figure out something to test about being sick? Or while she's home, maybe something involving chemical reactions in baking, showing different substitutions and results?
Reading over your post again, I realize I may be misunderstanding the time frame as well--you say "the topic" is due Wednesday, does that mean just come up with a topic, not do the project? I'm thinking along the lines of the way I did stuff as a kid, and from now to Wednesday would have been a huge amount of time for me to give myself, since I usually didn't start till the night before.
Anyway, good luck!
