This was perfect for Jackson & I to do on a sick day (we've had lots of those between the 6 of us in the last couple months!) He had so much fun. Step 1 was to sort the crayons and peel off LOTS of paper. I have since wised up and plan to use my exacto knife to speed up that process!
Thanks and credit here to my youngest 2 for the abundant broken crayon stash :x they completely destroyed a whole box of big brother's Crayolas... for fun apparently...what is wrong with my kids??
Then we filled the tray with similarly colored groupings of crayon bits. You have to use more than you think to make the finished crayons thick enough, they really melt down! I was so pleased to find this off brand silicone tray on ebay, the Lego brand ice cube tray can only be heated to like 130 degrees, this one can handle the 400 needed. And the finished "legos" are bigger than the lego brand.
Bake @ 400 for 10 minutes (almost exactly in my oven) And let them cool for longer than you think. You don't want them to snap when prying them out. (Besides, it gave me more time to peel another batch of crayons! Oi Vay.) I found it easiest to pull each crayon loose from the sides then peel back the silicone to remove. It peels right off!