Raising athletic children can be a shopping challenge. I have a gymnast and a short-track speed skater and both of them snowboard and skateboard as well. Those purchases really add up! Here are some US sources of equipment.
Skating
Baby Skates teach those little ones!
Reidell Skates for bigger skaters.
Gymnastics
Gym Digs US Made gymnastics leotards
Mats, Mats, Mats offers a variety of US made gymnastics mats and balance beams
Satara Leos US Made gymnastics leotards
US Glove for gymnastics wrist supports and more
Board Sports
Beer City Skateboards Made in Milwaukee
Mini-Logo Skateboards my son uses these
Revolution Snowboard Made in Utah
Unity Snowboards Made in Colorado
