LITMIR.BIZ

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was that?” Ms. Belfry said, although Oliver knew full well she’d heard him perfectly.

      Reticently, he spoke a little louder. “You need to create lift.”

      No sooner had he finished speaking than Oliver felt a blush creep into his cheeks. He felt the change in the room, the tenseness of the other students around him. So much for not having thirty pairs of eyes gawking at him; Oliver could practically feel them burning into his back.

      “And what is lift?” Ms. Belfry continued.

      Oliver wet his dry lips and swallowed his anguish. “Lift is the name of the force that counters gravity. Gravity is always pulling objects down to the center of the earth. Lift is the force that counteracts it.”

      From somewhere behind, he heard Paul’s whispered voice in a mock whine, mimicking, “Lift counteracts it.”

      A tittering of laughter rippled amongst the students behind him. Oliver felt his muscles stiffen defensively in response.

      Ms. Belfry was clearly oblivious to the quiet mocking Oliver was experiencing.

      “Hmm,” she said, as if this was all news to her. “Sounds complicated. Countering gravity? Isn’t that impossible?”

      Oliver shuffled uncomfortably in his seat. He really wanted to stop speaking, to have a small respite from the whispers. But clearly no one else knew the answer, and Ms. Belfry was watching him with her sparkling, encouraging eyes.

      “Not at all,” Oliver replied, finally taking the bait. “To create lift all you have to do is change how fast air flows around something, which you can do just by changing the shape of the object. So with your popsicle stick, you just need a ridge on the top side. That means that as the stick moves forward the air flowing above and below it have different-shaped paths. Over the humped side of the wing the path is curved, whereas beneath the wing, the path is flat and uninterrupted.”

      Oliver finished speaking and immediately pressed his lips together. Not only had he answered her question, he’d gone above and beyond in explaining it. He’d gotten carried away with himself and now he was going to be mocked mercilessly. He braced himself.

      “Could you draw it for us?” Ms. Belfry asked.

      She held out a board pen for Oliver. He looked at it, wide-eyed. Speaking was one thing, but standing in front of everyone like a target was a whole other!

      “I’d prefer not to,” he muttered out the side of his mouth.

      He saw the flicker of understanding in Ms. Belfry’s expression. She must have realized she’d pushed him to the edge of his comfort zone, beyond it even, and what she was asking him now was an impossibility.

      “Actually,” she said, withdrawing the pen and stepping backward, “maybe someone else would like to try drawing what Oliver’s explained?”

      Samantha, one of the brash kids who craved attention, leapt up and snatched the pen from Ms. Belfry. Together they went over to the board and Ms. Belfry helped Samantha draw a diagram of what Oliver was describing.

      But as soon as Ms. Belfry’s back was turned, Oliver felt something hit the back of his head. He turned and saw a ball of screwed up paper at his feet. He reached down and picked it up, not wanting to open it, knowing there’d be a cruel note inside.

      “Hey…” Paul hissed. “Don’t ignore me. Read the note!”

      Tensing, Oliver opened up the paper ball in his hands. He smoothed it on the desk before him. Written in terrible spider-crawl handwriting were the words Guess what else can fly?

      Just then, he felt something else hit his head. Another paper ball. It was followed by another, and another and another.

      “HEY!” Oliver cried, leaping up and turning around angrily.

      Ms. Belfry turned too. She frowned at the scene before her.

      “What’s going on?” she demanded.

      “We’re just trying to find things that fly,” Paul said innocently. “One must have hit Oliver by accident.”

      Ms. Belfry looked skeptical. “Oliver?” she asked, turning her gaze to him.

      Oliver sat back down in his seat, hunkering down. “It’s true,” he mumbled.

      By now, the boisterous Samantha had finished her diagram, and Ms. Belfry was able to turn her attention back to the class. She pointed at the board, where there was now a diagram of a wing, not straight but curved like a sideways stretched teardrop. Two dotted lines indicated the paths of air passing above the wing and below it. The flow of air going over the humped wing looked different in comparison to the flow going directly under it.

      “Like this?” Ms. Belfry said. “But I still don’t understand how that produces lift.”

      Oliver knew all too well that Ms. Belfry knew all this, but having just been pelted by paper balls had made him reluctant to speak again.

      Then he realized something. Nothing he did was going to stop the teasing. Either he sat there silently and got picked on for doing nothing, or he spoke up and got picked on for his intelligence. He realized then which he’d prefer.

      “Because with the air following in different paths like that, it creates a downward force,” he explained. “And if we take Isaac Newton’s third law of motion—that every action produces an equal and opposite reaction—you can see how the resulting reaction to that force, to the downward force, is that the air traveling under the wing creates lift.”

      He folded his arms and sat back against the chair.

      Ms. Belfry looked triumphant. “That’s quite right, Oliver.”

      She turned back to the drawing and added arrows. Oliver felt a paper ball hit his head but this time he didn’t even react. He didn’t care anymore what his classmates thought of him. In fact, they were probably just jealous that he had brains and knew cool stuff like Isaac Newton’s laws of physics when all they could manage was screwing up a ball of paper and aiming it at someone’s head.

      He folded his arms more tightly and, ignoring the paper balls smacking him in the head, focused on Ms. Belfry’s image. She was drawing an arrow pointing down. Beside it she wrote downward force. The other arrow she’d drawn pointed up with the word lift.

      “What about hot air balloons?” a voice challenged from behind. “They don’t work that way at all, but they still fly.”

      Oliver turned in his seat, searching for the owner of the voice. It was a grumpy-looking kid—dark, bushy eyebrows, dimpled chin—who had joined Paul in throwing the paper balls.

      “Well, that’s a completely different law at play,” Oliver explained. “That works because hot air rises. The Montgolfier brothers, who invented the hot air balloon, realized that if you trap the air inside some kind of envelope, like a balloon, it becomes buoyant due to the lower density of hot air inside compared to cold air outside.”

      The boy just looked more angry at Oliver’s explanation. “Well, what about rockets?” he challenged further. “They’re not buoyant or whatever you just said. They go up, though. And they fly. How does that work, smarty pants?”

      Oliver just smiled. “That comes back to Isaac Newton’s third law of motion again. Only this time the force involved is propulsion, not lift. Propulsion is the same thing that moves a steam train. A big blast out one end produces an opposite reaction of propulsion. Only with a rocket it’s got to get all the way to space, so the blast has to be really massive.”

      Oliver could feel himself growing excited as he spoke about these things. Even though all the kids were staring at him like he was a freak, he didn’t care.

      He turned back in his seat to face the front. There, smiling proudly, stood Ms. Belfry.

      “And do you know what all these inventors had in common?” she said. “The Montgolfiers and the Wrights and Robert Goddard, who launched the first liquid-propellant-fueled rocket? I’ll tell you what. They did things they’d been

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