Because my elder daughter really likes the parashot concerning the Mishkan, we started with the building of the Aaron Chodesh.
You just need a wood box that the children will cover with a gold paint,
two wooden sticks to paint in the same way, a printed image of the
Keruvim to glue on a gold cardboard and then on the top of the box.
Always on the top you can glue a golden cloth tape or ribbon.
Inside we put a golden plastic base and made two blue plasticine tablets, you can even write the Aseret Hadiberot on it with a needle.
My children like a lot to move the Aron Chodesh and then put it in a drawing of the Mishkan.