How racist is this poster?

The American Red Cross has apologized after the poster it produced featuring safety advice for public swimming pools drew complaints that it was racist. The poster, headed "Be Cool, Follow the Rules," depicts several children playing around a pool, with labels identifying their behaviour as “cool” or “not cool.”
The poster became the subject of ire on social media after one mother noted that it was predominantly white children in the poster labelled as “cool”, and non-white children labelled “not cool.”
Do you see anything wrong with the poster?