Many people misunderstand, at first, what it means to learn math at early age. They remember how they learned the multiplication tables for example—tedious and boring, hours of painful repetition that was certainly not the first choice of activities. None of this work is required of the children if concepts are offered and presented with manipulative materials to one child at a time or a small group of children. There is no lecturing to a group of children who are required to sit still and listen. The children learn each step with joy and enthusiasm until they are ready to move to the next step.
We also like using stories as one the techniques to teach match concepts. All of these books are all available through Amazon or other book stores; a quick Google search should turn up many options (including other books by the same authors) for you to enjoy with your children.
Inch by Inch by Leo Lionni
Busy Bugs: A Book About Patterns by Jayne Harvey
Counting Caterpillars and Other Math Poems by Betsy Franco
The Greedy Triangle by Marilyn Burns
The Go-Around Dollar by Barbara Johnston Adams
The Coin Counting Book by Rozanne Lanczak Williams