Ah yes, Estes model rockets. Built several, even one that was even a 3-stage. Launched that one only once as the third stage vanished. About 6 months later some boy scouts appeared at the house returning my rocket (printed my name/address on all rockets). They had come across it in a state park almost 50mi away.
Besides the usual fireworks like m-80s, cherry bombs, 4inchers, ect. We came across a tin of black powder, poured about a pound (.5kg) in a 2in pipe screwed the endcaps on with a length of cannon fuse. Not sure what to do, we leaned it against a fireplug, lit the fuse and ran like he*l. About a minute later a massive explosion and a geyser of water that shot 30ft into the air. Tried once to make nitroglycerine. Made about 100ml. To test it we threw it against the basement wall. Our experimet failed fortunately