These double-sided, write on, wipe off place mats by Melissa & Doug at Janie & Joe are made from high-quality and durable materials. These fun activity mats are ideal for use with Melissa & Doug's Learning Mat wipe able multi-coloured crayons and are available in a range of topics. Practice simple subtraction with this Subtraction Write-a-Mat. Great value for money, can be used again and again.