McGraw Hill Education has an online interactive “Math Toolbox” (as I like to call it). You can select your grade level (PreK-8) and then there are various game boards, story boards and workmats. There are also various manipulatives to use!
This is truly a thing of beauty! It is a GIANT list of children's books that teach math skills! It is sorted by what math skill you are trying to teach. Unfortunately, Pete the Cat and His Four Groovy Buttons is missing!!!