11 Something to Do with Pressure

CHAPTER ELEVEN SOMETHING TO DO WITH PRESSURE Boyle's law (proper noun). This law says that the pressure of a gas goes up as the volume of its container gets smaller. Just like if you squeeze one part of the balloon (like a dog leg or monkey tail), the size of the balloon decreases and the pressure increases. If you squeeze the dog leg really hard, the pressure will increase so much that the balloon will explode! POP! OVER BY THE SUPPLY TABLE, Elijah and Memito were arguing about the secret material that would make our rockets really soar. And I realized I hadn't figured it out yet either. All I knew is that it had something to do with pressure. And right now, honestly, I was feeling a lot of that. "Oh, I have to do something!" I said to Birdie, who glanced back at me with a confused expression. Heading to the middle of the lab, I explained, "I've got to make an educated guess." I stopped in front of the supply table. "If all the supplies are here, one of them should be the special material," I said, looking over at Tala for

confirmation. "You're right." Tala gave a thumbs-up. "It's definitely right here." Jeremy flipped a coin into the air. The streak of purple in his blond hair flopped in his eyes. "I bet which one of you would get it right." He pointed at Memito and Elijah and then me. "I said you, Kate." "You shouldn't bet." I shook my head, but privately I felt a little happy about it. And surprised, since sometimes in the past, Jeremy wanted me to lose, whether it was a pickup game of soccer or the science fair. Memito scooped up a plastic water bottle. "How about this?" Tala shook her head. "It's essential but not a secret way to make the best rocket ever." "The nose cone? Right? That's it?" asked Elijah. "Nope," said Tala. "How about the sequins?" piped up Birdie, who was standing a bit farther away from the table than the rest of us. My heart gave a little squeeze of happiness. She sounded almost like her regular self. "Sequins are just decoration," said Tala. "Decoration is essential." I nodded at Birdie's nose cone with its glittery swirls.

"Exactly. I mean, can you imagine going to a play without a set or curtains or costumes?" said Avery. "It would be so humdrum," she over-enunciated as if she were onstage. "What do you think, Kate?" asked Jeremy. "I mean about the special material?" My eyes swept over the materials. The heaps of bottles, colored paper, corks, little sequins, ribbons, and glitter for decoration. "I think it's the cork," I said. "Because it seals the bottle to build up pressure, which produces the thrust." "Good science," said Tala. "But still, no." That's when Jeremy walked to the table, picked up a roll of toilet paper, and wrapped some around his neck. "I have no clue what it is," he said. "But look at me; I'm a mummy!" "Actually, he's much more than a mummy," said Tala. "Jeremy has the answer."