NJSLA Practice Test 1

The Silver Bridge

¹The night before Engineering Night, my bridge sat on the kitchen table like a trophy nobody had awarded yet. Two hundred craft sticks and nine evenings of work stretched between two stacks of cookbooks. I had even painted the railings silver. Ms. Adebayo had reminded our class that the judges at the library would care about only one thing—how much weight each bridge could hold before it cracked—but I figured a little shine could not hurt.

²“Looks great, Ines,” my brother Gabe said, leaning over it with a bowl of cereal. “Is it supposed to dip in the middle like that?”

³“It doesn’t dip,” I said. “That’s just the light.”

⁴Gabe shrugged and carried his cereal to the living room, but his question followed me around the kitchen like a fly. Two weeks earlier, Callum Hart had slid his notebook across our lab table. He had drawn a bridge covered in small triangles, each one braced against the next. “A triangle can’t change its shape unless one of its sides breaks,” he had said. “A square can fold flat. We should brace every section.” I had looked at his sketch for about three seconds. My design used long, straight beams, like the bridge over Larchmont Creek, and it was already half finished at home. “Mine is simpler,” I told him. “You’ll see.” He had closed his notebook and built a bridge of his own.

⁵Now I decided to run a test of my own. I laid a ruler across the center of the deck and set my math textbook on top of it. The bridge held. I added Gabe’s science book. The bridge held, but the silver railings leaned outward, the way a person’s elbows stick out when carrying something too heavy. When I added the dictionary, I heard a sound like a knuckle cracking. The deck folded into a shallow V, and the dictionary slid onto the table with a thump.

⁶I did not cry, exactly. I sat down and stared at the broken middle for a long time. Every square I had built had simply leaned over until it became a flat diamond. Callum had described exactly this, and I had not listened, because listening would have meant admitting my plan had a problem.

⁷Mom came in, looked at the bridge, and then looked at me. “What’s the damage?” she asked.

⁸“Just the middle,” I said. “But the middle is the part that matters.”

⁹She pulled out a chair and sat down across from me. “Then fix the middle. You have until six o’clock tomorrow.”

¹⁰I messaged Callum before I could change my mind. “Can you show me how you braced your sections?” I typed. My thumb hovered over the screen for a full minute before I pressed send.

¹¹He answered with a photo of his notebook and one line: “Glue the diagonals first, and let them dry before you load anything.”

¹²I worked until almost eleven. I did not repaint anything. I cut new sticks and glued them corner to corner across every square, so that each section became two triangles. The new pieces were unpainted and messy, and the glue dried in cloudy drops. The bridge looked worse than it had that morning. When I pressed gently on the middle with two fingers, though, it pushed back.

¹³At Engineering Night, my bridge held forty-one pounds before a single joint split. Callum’s held fifty-three. I came in fourth and he came in second, and when the judge handed him his ribbon, I clapped loudly enough that he turned around and grinned.

¹⁴On the ride home, Gabe flicked one of the unpainted sticks. “It’s not very shiny anymore,” he said.

¹⁵“No,” I said, running my thumb along a cloudy drop of glue. “But now I know why it holds.”