In the episode "Mind Your Business," the saboteur sabotages Raven's business by pouring lots of kernels in the popcorn machine. However, the saboteur pours the kernels into the glass holding box instead of the pot, so the kernels would not have heated up enough to cause the popcorn mountain.
The school that Raven goes to is called Bayside. This is the name of the school from the hit TV show Saved by the Bell. They also used the set of that school as well and if you've seen Saved by the Bell you will be able to tell.