Terrarium drama

This week, due to the generosity of a student, toads were introduced to our classroom terrarium. Overnight we discovered that toads are efficient predators. They reduced the population of bugs in their new environment to the large katydid the first day. The class continued to supply bugs as they were able, but I am quite certain that the toads need to be out and about getting ready for hibernating. They were released today down near the lake. Upon return to the classroom there was a significant reduction in interest in the now ravaged terrarium.
I underestimated the amount of ongoing interest there would be in the bugs in the corner. When there is any lull in the classroom activity or an perceivable movement amongst the bugs, at least four people will rush to the corner to see just what it is that is going on. Due to their careful watch, they have been able to witness the demise of a couple of the bugs. This is, of course, 'the point' of the whole project. It is good for them to be curious and observant and interested. It is probably even good for them to move across the room periodically as long as they return to their seats just as quickly.
We are looking to evacuate the terrarium for the winter however. I suppose a few bugs could stay, but I wouldn't expect them to live long. We would appreciate a caterpillar choosing to spin up its cocoon for us to observe, but as of yet, the caterpillars have merely disappeared (consumed by crickets?) and have been quartered in separate containers.If the kids continue to memorize their verses, the 'memory tank' will continue to gain components and we will, soon enough, have a whole new world to observe.