@MsClean - Hi, I just wanted to share a piece of advice with you about drying your calabash gourds. Just so you're aware of it ahead of time, gourds tend to put off a very nasty odor while they're going through the drying process.
You might want to carefully consider an appropriate place for them to dry besides your classroom. That would be a terrible distraction to withstand for two months. Otherwise, it should be a fun and exciting learning project for your class.