RENEE MONTAGNE, host:
It's MORNING EDITION from NPR News. I'm Renee Montagne. Good morning.
STEVE INSKEEP, host:
I'm Steve Inskeep. Today's installment of Your Health will explore the food that young people eat. In a moment, a teenager explains why she went vegan.
First, we'll listen as kids learn all about calories. Everybody has a rough idea about which foods are high calorie. But one school in Philadelphia is teaching fourth graders the science.
NPR's Allison Aubrey reports.
ALLISON AUBREY: A year ago, the playground at Gomper's Elementary was nothing but a slab of asphalt. There are no swings, no slides, no monkey bars. But last spring, all that changed.
(Soundbite of children playing)
AUBREY: That's when Joe Cifelli, a professor of education, and his colleagues at nearby St. Joseph's University decided to build a playground.
Professor JOSEPH CIFELLI (St. Joseph's University): It's fabulous. They were just tickled that we're able to do this.
(Soundbite of children playing)
Unidentified Child #1: It's fun.
AUBREY: Cifelli has become a fixture at this school. Once a week he volunteers, teaching nutrition science to fourth graders.
Prof. CIFELLI: Ultimately what I'll do is bring the classroom out here and we'll talk about, you know, doing chin-ups or doing some real things and kind of relate that back to the use of energy in our bodies.
Okay, good morning, boys and girls. It's good to see everybody...
AUBREY: Inside, Cifelli's classroom becomes a laboratory. He uses techniques that won't bore kids to tears or make them feel guilty about their favorite foods.
Prof. CIFELLI: How many people like cheese curls? Oh, look at this.
AUBREY: As Cifelli tears open a bag, hands fly up into the air.
Prof. CIFELLI: How many cheese curls can you eat at one time?
Unidentified Child #2: About three?
Prof. CIFELLI: Three? Who can eat more than three?
Unidentified Child #3: I ate the whole bag.
Prof. CIFELLI: You eat the whole bag. Okay, great. Well, she's like me, because I would eat the whole bag. But what we have to figure out this morning is, is there energy in this? I want you talk to the guy next to you and see what you can come up with.
AUBREY: The lesson here is that food equals energy. And calories are simply a unit of measurement for the energy. The concept's brand new to the kids.
Prof. CIFELLI: Okay. What do you think? Does the cheese curl have energy?
Unidentified Children: No.
Prof. CIFELLI: Okay. How many people say no? Oh good. How many people say yes? We're about half and half - say yes and some say no. Okay, let's see...
AUBREY: Cifelli knows that if he doesn't blurt out the answer, kids may lose interest. He wants them to figure it out. So to make this lesson come alive, he sets the cheese curl on fire.
Prof. CIFELLI: Just going to put a little flame under it. Okay. And we're going to see what happens. Oh, look at this.
AUBREY: Cifelli puts the cheese curl on a rod under a beaker of water, then takes the temperature of the water. As the flame grows, the kids inched forward on their seats.
Prof. CIFELLI: Oh, look at this. Can you see it? Robert, describe what you see.
ROBERT (Student): Well, I see the cheese curl's burning from the fire and the fire is starting to have smoke come out.
Prof. CIFELLI: Okay, what else? What do you think is happening to the water, Dantes?
DANTES (Student): The water is evaporating.
Prof. CIFELLI: That's a good word, evaporating. Okay, and notice that it burns on its own. What does that tell me? Yeah. That has energy in there. That's right, okay.
AUBREY: So the cheese curl has energy, but how much? How many calories?
To figure it out, Cifelli dips the thermometer in the beaker of water and takes a second reading.
Prof. CIFELLI: Okay, we actually now have a temperature of about 45 degree Celsius - 45 degree Celsius, okay? So we could see that the temperature has changed. You have your calculators there. Compute what the temperature change was.
AUBREY: As little fingers push digits, Cifelli explains that the difference between the old temperature and the new temperature is the key to calculating calories.
Prof. CIFELLI: Okay, somebody has an answer? Tanara?
TANARA (Student): Twenty-two.
Prof. CIFELLI: Twenty-two degrees Celsius. So the water changed 22 degrees Celsius as a result of cooking it, basically, with the energy that was in the what? In the cheese curl.
AUBREY: Since the students are nine years old, Cifelli doesn't expect them to walk away with the precise understanding that a calorie is the energy needed to increase the temperature of one gram of water by one degree Celsius. What he's aiming for is a broader understanding.
One student, Dianthe Willis(ph), says she knows cheese curls are junk food. So she was surprised to see they have so much energy.
Ms. DIANTHE WILLIS (Student): When I saw all of the energy in the fire, and I was thinking, maybe that is good for you.
AUBREY: Which leads into Cifelli's next lesson, which will focus on how much of what kinds of energy are best for our bodies. He says Dianthe's question is a good starting point.
Prof. CIFELLI: That gives you an entré into the conversation. So you know, I firmly believe in the notion that learning is mostly talking and that teaching is mostly listening. So the idea is that we can get them to talk to each other about the stuff, that these kids are now using terms like calories and energy and saturated fats.
AUBREY: Cifelli's hope is that this knowledge empowers students to make healthy choices. But he knows this won't happen overnight. He learned this last year when he invited a few students who just finished his course to join him for lunch at the cafeteria.
Prof. CIFELLI: They just filled up their plate with everything they could. You know? And they had big fries and hamburgers and it was funny because one girl said, oh, I'm watching what I'm eating now because of what I've learned in the class. So she didn't take two hamburgers. She only took one, you know.
(Soundbite of children playing)
AUBREY: Cifelli says it's moments like this he takes comfort in knowing just how much time these kids are spending on the new playground. Allison Aubrey, NPR News.
INKEEP: You don't have to burn your food to figure out the calories. The professionals do it for you and have all the fun at npr.org/yourhealth.