What to do with all those broken bits of crayon rolling around the playoom, under the couch, under my shoes?! Melt them into crayon cakes! That's what we did and it serves many purposes. Mr 4 learnt all about the properties of wax, recycling, cleaning up(!) and it kept them quiet for an hour between the finding the broken crayons, peeling the paper off, sorting the colours and then using the new crayon cakes... such an easy activity! All you need to do is break up your reject crayons into small enough pieces to fit into your cupcake tray, put the tray into a moderate oven for about 10 minutes or until each "cake" is melted, pull them out, give them a swirl with a toothpick for a good rainbow effect and allow them to cool and harden (which only took ours about another 10 minutes). Voila!