A.H.
Make crayon cakes - this is so much fun.
Take a whole bunch of old/broken crayons and take the paper off of them. Have the boys help you sort them into piles by color. It's ok, even better if they break the crayons into little pieces during the process.
Fill up the cups of a cupcake pan with piles of the broken crayons...you can keep all of the same colors together, or make fun combinations like pink crayons and brown crayons, or a rainbow mix. Try not to overflow the cups - fill them about 3/4. Bake them at 350 - the crayons will melt and form "crayon cakes," perfect size for little hands to color with, and so fun because they will have different colors or hues when coloring. Using the gold and silver crayola crayons in the mixes are fun too for a sparkly finish. Once the crayons are totally melted, pull them out of the oven and give them some time to cool completely before pulling them out. You can pop them in a freezer for a minute while cooling, just don't leave them in there too long or they will crack a little later.
Get some construction paper and use the crayons you made to make Halloween or birthday cards for family.