The aim of this activity is for pupils to explore how a new counting system might work and how our number system works. This is great prep for introducing binary, base 2 or other bases.
First explore the tally counting system, pupils could be given counters, some things to count.
Then on to counting to 10 using both hands and counting to 12 and 60 using one hand, make links with 12hrs, 60 minutes.. examples here.
Then look at the symbols used for numbers, line for tally, digit one etc.
Ask question such as what happens in tally when you get to 4 and you add one more (5)? What happens when you get to 9 in out number system? Model by counting up how our denery system works. Do so using a grid. Show the purpose of a zero.
The main part of this activity is giving pupils a piece of paper and a pencil and creating their own number system and symbols for each number