Collin Graver, a 15-year-old homeschooler from Avondale Estates, always draws attention when he goes for a ride on his new bicycle.

The wheels are round pieces of wood the size of big manhole covers. The frame is a wooden box several inches wide. Everything is the same color -- light brown.

Except for the metal pedals and the screws holding it together, every piece of the bike was cut from a single piece of plywood.

The bike is hardly meant for the Tour de France. It weighs roughly 50 pounds, only goes six miles per hour and doesn't have brakes or gears.

"It probably has eight miles on it total," Collin said Monday.

He decided to make a wooden bike when he found himself with extra time between math studies.

"I'm not sure how I came up with the idea," he said, "but suddenly it was there."

Collin said he spent about 35 hours working on the project, including a trip with his mother, Angie Graver, to buy the plywood at Home Depot.

His mother said being homeschooled helped Collin because class time is flexible. When he wanted to work on the bike, Collin could just walk downstairs to the shop.

He spent a few hours drawing plans on paper and based the bike's dimensions on those of his mountain bike. Collin said the design is original, that he'd never seen a wooden bike online or in a book. After he completed the bike, he looked online and saw others.

Instead of a chain, his bike has three interlocking sprockets -- two with 28 teeth, one with 21 teeth.

"For every three times the pedals go around the wheels go around four times," he said.

It also means the pedals turn constantly when the bike is in motion, even while going downhill. The ride is very bumpy.

He put the bike on the road about 10 days ago. The second time he took it out, a motorist stopped, shot some video and posted it on YouTube. He didn't even get Collin's name.

Collin is handy and enjoys working with wood in the basement shop at his house.

He's built, among other things, a four-story playhouse in his backyard, some bunkbeds for a homeless shelter, a desk, a chess set, window boxes for the house and three floats for the Avondale Estates Fourth of July parade.

He has other projects in mind, perhaps a pedal car or a solar-powered car. Keep you eyes peeled.