Have fun breaking the ones that need to be smaller, or...
...use karate moves to break them by hand!
This is about the size you need them to be.
Fill each mold on a mini heart-shaped muffin pan to the top with crayons. We made some rainbow and some the same color scheme. Don't use black, dark blue or brown crayons, as they tend to overtake the other colors.
Bake them at 250 degrees for 20-25 minutes in a silicone pan or 10-15 minutes in a metal pan. I bought Wilton silicone pans at Ben Franklin, but I bought the last two. You can buy them at Michael's and probably Target. The silicone pans make it easier to pop out the crayons.
Not only are then cute, when you use them they write in a rainbow of color. Have fun, and if you do the craft, let me know how they turned out.