"What's the first thing we do when we get to our bike?" David Gesualdi asks his second-graders. "Check the air!" they yell back at him.
His 19 students are sitting in a semicircle in the gym at Walker-Jones Education Campus, not far from the U.S. Capitol.
Decked out in blue helmets, hair nets (for lice protection) and bright orange mesh vests, their eyes shift impatiently between their phys-ed teacher and the racks of shiny new BMX bikes behind him.
First, though, he walks them through the A-B-C's: "Air. Brake. Chain."
This is all part of the D.C. public schools' mission this year to teach every second-grader how to ride. In partnership with the city's transportation department and private donors, the district bought nearly 1,000 new bikes. Those bikes will rotate throughout the year to every elementary school in the city.
As Gesualdi finishes his safety lesson, the kids rush to get on the bikes, jostling for one that fits. In seconds, they're off — zooming in circles around the indoor gym.
"Excuse me!" yells one girl as she whizzes past me.
There's a wide range of skills. Mehki House is fast, doing tricks and twisting sideways on the bike. Until ... he wipes out.
"I was driving too fast and I fell," he explains as he gets back up and takes off.
Others, though, are struggling. Like Walter Young. Walter has one foot on each side of his bike. He's waddling along, dragging the bike beneath him.
"This is a problem," he moans. "I bet everybody in the world knows how to drive a bike except for me."
This range in ability, it's a challenge for their teacher.
But Gesualdi says he's not about to slow the good riders down. "Even though it might not be new to them," he says, "having a chance to show off some of their skills is really exciting."
He mentions Mehki — the boy doing tricks: "It's something that I'm trying to channel and make him more of a model for the rest of his peers."
But this class is not just about how well you ride. It's about riding safely. To mimic a city street, Gesualdi has set up a course in the gym — with stop and yield signs and arrows to mark turns.
He gathers the bikers near one end of the gym and pulls out a few students to demonstrate the path. Gesualdi does the play-by-play as one boy navigates the course.
"Did he stop?" he asks.
Yes, the class answers. Gesualdi turns to the group: "What's really cool is he came off his bike to make sure he stopped."
Eventually all the 7- and 8-year-olds make their way through the course, Gesualdi nudging and cheering them on the whole time.
One student needs a reminder to follow the arrows on the ground; another wins praise for good safety skills: using hand signals as he turns.
And Gesualdi assures the new riders that he's there if they need him.
Even Walter is making a little progress — singing as he tries to balance on two wheels. "Oh no!" he says. "I almost had it."
Gesualdi is confident Walter will be riding before he leaves second grade and says he's teaching these kids something they'll hold on to long after they graduate.
"It's a skill that's not only a good fitness skill, but its something that's really helpful as they get older," says Gesualdi.
When the class ends, the helmets come off and the bikes go back on the racks. Students compare notes: One kid says he "got air." Another didn't fall off. They look pooped.
"So was that hard?" I ask them.
A boy grins up at me: "It wasn't hard work. It was fun."