Egg carton craft

I have been saving egg cartons for about 18 months to try some craft activities with the boys. There are lots of good pictures on Pinterest and the like of people making egg carton caterpillars and trains. It turns out that it isn't as easy as it looks to attach them together with pipe cleaners and, at 3 and 4, the boys were fairly uninterested anyway. After I had a go, W turned the egg box lid into a boat for his lego men which was much more successful.