USA Ninja Challenge is a year-round obstacle course training program that combines basic skill sets from gymnastics, climbing, cross-training, and track & field. The sport of Ninja is quickly becoming the most fun and creative way to meet the physical needs of today’s kids! USA Ninja Challenge is open to boys and girls ages 4 to 17. Our class program has 6 levels to master with a wide variety of progressions, drills, and challenges.