I am trying to teach math facts to my son too. I've used the 100 board to teach my son simple math facts, base 10, skip counting, and numeral order
This is the board we have used.
When we first started, I only used 1-30 chart and later worked my way up to 1-50. It was easy, just let your child match the number tiles with the numbers on the board. When he is getting better, remove all the numbers from the board. Ask your child to build his own "number board' using the blank grid chart. A child who has worked with the board for a while will know exactly where each number is. For example, if there is number 5 on the board, my son will know that 15 is below 5 because 15 is 10 more than 5. 6 is on the right because it is 1 more, and 4 is on the left because it's 1 less than 5.
I also use the arrow to teach number order too. The arrow is showing the number direction.
" --->" means 1 more or move one box to the right. "<---" means 1 box to the left, and it's 1 less. Arrow up means 10 less, and arrow down means 10 more.
2 arrows represent 2 boxes, and etc.
Supposedly, we are doing +2 and -2. My son holds the board in his hand, looks at the equation, and use the board to find the answer.
To me, this is better than memorizing math facts because he visualizes the board in his head and understand number orders. I am hoping to take a way the number board and just let him give me the answers from memory.