Based on NCETM videos
Colour, laminate, store in plastic wallets as 1s, Xs, etc.
https://www.ncetm.org.uk/classroom-resources/secmm-using-mathematical-representations-at-ks3/
Mathematical thinking is central to how pupils learn mathematics and includes looking for patterns and relationships, making connections, conjecturing, reasoning, and generalising. Pupils should actively engage in mathematical thinking in all lessons, communicating their ideas using precise mathematical language.