On Your Mark. Let their creativity run wild, but not too wild. Heres a set of 10 washable broad tip, no-stress markers that maximize creativity and minimize stains. You buy, Yoobi gives for every awesome Yoobi item you buy, Yoobi will donate another supply to a classroom in need right here in the USA. Age Group: 1 Year and Up,1,5,18 Years and Up.