I signed Hannah up to attend a library program called "Bright Beginnings". Her teacher was awesome and had some great ideas. This is the number kit they passed out to each child. There are die cut letters from 1 to 10 and bear paws in 10 different colors. There is only 1 white paw, 2 black paws, 3 brown paws, etc.
1st you lay out the numbers from 1 to 10.
Then pick a color (it doesn't matter which one) and count how many paws there are of that color. Place your paws under the correct number. Line them in groups of 2.
Now each number that only has pairs is an even number.
All numbers that have a paw by itself in a row is an odd number. You can also point out the pattern that your number line makes. Odd, Even, Odd, Even....
You can also stack the paws to see the difference in height between numbers.
Looking between 6 and 7, there isn't much of a visual difference, so with younger children, you could show an example like this.