I am sure many of us would have been taught in our childhood days to count the sheep as we sleep. Even though that was taught to make us sleep faster, it served a very important role in teaching us how to do mathematical additions.
The key to understand is that children will be inclined to do such mathematical exercises that don't require much efforts. And since in the bed they had nothing else to do, the counting sheep exercise was a much effective one.
So the first thing that we agree upon is that the mathematical exercises must be easy to ensure that the kids don't loss their interest.
Maths is an intangible concept. And one of the key attributes of mathematics is counting. When we count some physical thing, we are adding a tangible attribute to mathematics. This physical counting can build an additional understanding of mathematics. When you are teaching mathematics to your children, make sure that you make them use their hands while counting. When they use their hands, their visual senses will make it easy for them to understand what is 2 +2 ? This is the most easiest way to make children understand simple addition calculations. Children don't know what 2 is? But they do know what 2 apples means? It means one apple and one more apple.
Another good way of developing a kid's understanding about mathematics is through the use of numbered building blocks. The visual printing of numbers on mind can help a kid differentiate between two mathematical numbers.