ELC have got their range of Bits & Basics art and craft stuff on BOGOF just now. Picked up 2 boxes of 20 chunkie chalks for only £1.50 instore making them only 75p each. They're chunky and easy to grip first time chalks. Plenty to choose from to keep the kids amused over the holidays i.e. crayons/paper/pens all on BOGOF. I only wanted the chalk though as I've paid £1 for 5 measly chalks so this is a bargain and they don't break easily.
Offers are online as well but the chalk doesn't show as being BOGOF but it is definitely instore. P&P is £4.95 unfortunately if you order online.