Boys just love the trash-bag "leather" jacket -- and the cardboard cycle that lets them throttle past the fairy princess to the candy first!
If your child prefers riding horses to Harleys, you can trade the bandanna for a cowboy hat and modify the sandwich-board design to create a suitable mount.
To make the bike: Draw a simple side view of the front and back halves of the bike, each on a separate sheet of cardboard. Draw an approximately five-inch-wide strip down the forward part of the back of the bike and the rear part of the front.
Carefully cut out both shapes, then trace and cut out another copy of each one. Fold in the rectangular panels on both front pieces, affix strips of double-sided tape to one, then press the two panels together. Tape together the front edges of the wheel, too. Repeat for the two rear pieces.
Now, cut the shoulder yoke out of the 12- by 30-inch piece of cardboard, testing to make sure the hole fits over your child's head and neck. Use mounting tape to attach the yoke to the bike's front and back. Paint the bike and let dry.
Next, cut holes for the handlebars and footrests (the same diameter as the paper towel tube). Cover the tubes with foil and insert.
To make the "leather" vest: Cut a hole in each top corner of the trash bag for the armholes and collar. "Hem" the sides of the collar and vest with masking tape. Trace the collar onto poster board, then cut out. Make a center cut up the vest front. Turn the vest inside out and insert the cardboard in the collar. Use electrical tape to fashion zippers and buttons.