The primary colors - in Hebrew.  

red - adom

yellow - tzahov

blue - kakhol

Using a red, a yellow and a blue piece of paper (or crayon in each of these colors) hold one up and say the Hebrew name.  Then mix these up and ask your child to point to tzahov, point to adom, point to kakhol. Ask your child to show you a crayon that is kakhol, a crayon that is adom, a crayon that is tzahov.  Send your child to find a Lego piece that is adom, a fruit that is tzahov, a T-shirt that is kakhol... Stick to these three colors (the primary colors) and repeat often so that your child remembers the colors in Hebrew.  If this is too challenging, play the same game using the words in English.  You can also see how many blue things there are on a picture in one of your story books...

 

Choose 10 colors: red and orange and yellow and green, blue, and indigo and violet. These are the colors of the rainbow! Add brown, black and grey (or pink:)

Draw one yellow sun. 

Draw 2 blue clouds.  

Draw 3 people.  

Draw 4 flowers.

Draw 5 ants. 

Uh,oh, It's starting to rain.  Draw 6 raindrops. 

Using red and orange and yellow and green, blue, and indigo and violet. Make a rainbow. Those are the 7 colors of the rainbow.

The rain stops and out come the insects.

Draw 8 little caterpillars.

Draw 9 butterflies.

Make 10 little buzzing bees flying all around the page.