Learn at home with help from The Wonder Years/Hallmark actress, math whiz, and New York Times bestselling author Danica McKellar using her acclaimed McKellar Math books! Bathtime will be squeaky clean and sneaky smart fun in this original board book that gives your toddler a head start on learning math, all as part of your daily at-home routine!Take one messy baby, two busy feet, three rambunctious friends, four wayward ducks, and five floaty bubbles--and get a tubful of fun as one family's bathtime routine turns into a nightly ritual they can "count on"!Danica McKellar uses her proven math success to show children that math is all around us as she cleverly introduces the early addition concept of "counting on"--the idea that when we add 1, we can get the answer by simply counting on to the next number. This next book in the McKellar Math line shows that even washing your hair can be full of math fun!