Popping Rockets: Inventions & Engineering

Ellie was perplexed. “Mine still isn’t blowing up!”

She stared at the small white film canister on the ground in front of her, waiting and waiting for it to “pop”. Teacher Tracy Pluim picked up the canister and flipped open the cap.

“That one was ready, but just didn’t go,” he assured Ellie.

Ellie refilled her canister with water and broke an Alka-Seltzer tablet into quarters. “I’m adding a tablet, one quarter of it, and it’s going to blow,” she said, confidently.

“I think it’s a carbon dioxide solution,” said Teacher’s Assistant Britta.

Ellie placed the canister upside down in front of her and waited. “It makes the water fizz,” she said about the tablet. “It has a reaction and it blows!”

A canister nearby gave a slight “ppppfffttt” and fell over. “It didn’t even go very good!” said a disappointed A.J. But he wasn’t deterred by his anti-climactic result. Try and try again.

Rhys sat on the ground, waiting patiently. “It takes a while,” he said. He leaned in to check the canister. “Yeah, it’s still fizzing.”

Suddenly, “POP!” “Oh, my gosh!” Rhys exclaimed, falling back onto the concrete, his eyes big.

Ellie’s third attempt was not looking good several minutes in. “I hope it works,” she said. Getting impatient, she bent down, about to pick it up, when it suddenly POPPED and she jumped back in surprise. “So one-quarter works better!” she concluded.

Luke said they were instructed to try different amounts of the tablets to determine which would work best for the actual launch of their paper rockets. “That’s what we were testing,” he said. “We tried one half, and then three quarters. One just sat there and the other, the three quarter piece, exploded, but didn’t go very high.” Like Ellie, he also found that the one-quarter piece worked the best.

When it was time to launch the rockets, students lined up against a wall, slipped the uncapped canisters into the rocket tube and waited for the countdown. At “One”, they quickly capped the canister, set it upside down and ran to the “observation deck”. A couple of rockets exploded right away, and others took their time.

Luke’s didn’t pop until he picked it up. “Mine exploded in my hand!” he laughed.