In the 7th grade science class, I built the plaster of paris volcano. It had a 5 pound coffee can inside I’d filled with a mix of saltpeter, sulfur and sugar. I set it off in the grass between the science wing and the cafeteria. It sounded like a volcano all right. And all the sulfur dioxide gassed everyone. First our class, then the wind sent it into all the office people that came to watch. Then the wind changed again and blew the cloud into all the open windows of the cafeteria that was serving lunch at the time. I got an A for gassing the school.
Good times!