The other week Abbie was really excited about gathering up all the snails she could find in the yard. She put them all into a "snail home" and we gave them leaves and grass and fruit. I have no idea what they ate. But that gave me one idea: keep a log of all the snails in the yard -- as you find them, record their stats (weight, size, where they were found), somehow tag them (a dab of paint), and release them back. If you catch the same one, note where it was before. That's the raw data gathering step. Then at a later date, perhaps do an estimate on how many snails there are per square meter, their average range, lifespan?, etc. Depending on what data you get....