Any advice on home petri dish experiements

Hey all,

I am going to attempt to do an experiment with petri dishes at the school I am studying at in Nicaragua. I’ve managed to track down unflavored gelatin, but most recipes call for boullion cubes, which I have been unable to find. The only thing I can think of is blending some meat to add to the gelatin, but I’d prefer to avoid that. Can I get away with just Gelatin and sugar? For the actual dishes, I plan on just getting some foam coffee cups, cutting them down a bit, and then covering with plastic wrap and rubber bands. Any problems there, or will that probably work?

Any other tips, related activities, or ideas would be greatly appreciated.