Primary 2/3  looked at the order of numbers up to 20 by using  a line 0f 20 playing cards. They took it in turns to turn a card over and say its position, ie ” 3 of hearts- second” etc and recorded this on a whiteboard. They practised adding on 10 more or less by using a hundred square. One person chose a number and the other tossed a coin. If the coin was heads they added on 10 and if it was tails took away 10.The hundred square could be used to check your answer.