One of the pieces in Toca Boca’s lively new line of kids’ clothes—debuting in 1,700 Target stores nationwide later this month—is a coral-colored T-shirt of a mean-mugging sloth donning a baseball cap, with the word “Fast” printed underneath. It’s a piece that the company has found tested well across ages and genders, from younger girls to those harder-to-engage 9- and 10-year-old boys. As Mathilda Engman, Toca Boca’s design director, puts it, “It’s a silly humor and quirkiness that resonates with both girls and boys, and doesn’t fall into gender stereotypes.”