Some kids learn differntly. There are different ways of presenting information, visual, oral, hands on. Some kids have a hard time with conceptual math. Try to make it fun.
Get M & M's and practice adding and subtracting! When your done you get to eat them! Try for groups of ten and whatnot using graham crackers or something that comes in blocks of ten, maybe a chocolate bar. If you don't like the idea of food you can cut out paper with blocks on them.
My sons thought math was stupid and they would never do math for anything they would need. My mom used to help me do math at the grocery store, and so I did that with my boys. Compare two products and divide and multiply to figure out how much per ounce or pound etc.
Also with my boys I also showed them how cooking required math including fractions (while making cookies and pancakes). Doubling recipes helped them learn to add fractions. We had fun with pizza and pies as great examples of fractions too! Also with pizza and pies and other food can help with division and multiplication. Ask them how many pieces you will have per person etc.
These are suggestions for practical ways to show kids math and help them see the value. I hope some of them help!