I remember a Halloween in the early 1960's when I went through this change. Since I was the studious sort, not the juvenile delinquent type, my Haunted House was well... a little weird. After all, one must admit that a Volcanic Pumpkin is a far cry from a Haunted House. I don't remember where I got the idea, but I think it must have been from Mr. Wizard.
Those of a certain age will remember Mr. Wizard, a.k.a. Don Herbert, who used to host a Saturday morning TV program creatively titled: "Watch Mr. Wizard" which aired on NBC from 1951 until 1972. Mr. Wizard persuaded me to take various objects and foodstuffs from the kitchen and put them together in creative combinations that my mother viewed with some suspicion.
This particular Halloween, I had recently learned that if you grind anything up small enough and mix it with air, you can get it to burn. Mr. Wizard had probably demonstrated this useful trick with something exotic like titanium powder (which burns REALLY REALLY well, by the way). Thankfully, I didn't have access to any titanium powder, so I had to make do with what I did have, which was flour. Plain old bleached white flour.
We set up a card table just inside the front door and covered it with a sheet. The sheet hid the studious looking fellow under the table, and the table supported a large, carved pumpkin illuminated from within by a candle. Also inside of the pumpkin was a funnel, which was connected to a tube, which ran behind the pumpkin and under the table. If you put a few teaspoons of flour into the funnel, and then blew on the tube just right, you caused a cloud of atomized flour to shoot into the air. And damned if Mr. Wizard wasn't right, the flame from the candle ignited the flour and an amazing shower of yellow sparks shot from the top of the pumpkin!!
We were set. We turned out the inside lights to maximize the effect and lay in wait for the first set of trick-or-treaters to ring the doorbell.
The doorbell rang, and we carefully and slowly opened the door, while hiding behind it. "Trick or Treat!" they yelled. But there was nothing to be seen save the ghostly pumpkin glowing eerily in the dark. A puff of air and a shower of sparks erupted from the pumpkin along with a satisfying crackle and roar. The effect was memorable.
Of course, an accomplice sibling then appeared from behind the door and handed out the candy. No one actually turned and ran, and no one went without their treat. It was, however, a tremendous hit. Pretty soon we had return visits; not for candy but for an encore performance. Groups of parents came by saying they had been told to go down to the Homchick's and see the exploding pumpkin. Many times the doorbell rang, and many many times a puff of air sent atomized flour into the air. All in all, it was an extremely successful experiment.
The next morning, with the sunlight streaming in the windows, we saw the unintended effect of the prior night's activities. Every surface in the house was covered with a fine dusting of white flour. All of the furniture, the floors, the curtains, the windows; everything looked like it had just been hit by the seasons first dusting of snow. Mother, being the kind soul she is, thought this was just as funny as the volcanic pumpkin, and cheerfully cleaned up while we were at school. I don't believe, however, that I ever got permission to try this stunt again.

