Developing mental arithmetic skills

Bar modelling: subtract a single digit from 2-digits (easier)

Bar modelling: subtract a 2-digit number from a multiple of 10.

Subtract a 1-digit number from a 2-digit number using a number line.

Bar modelling: subtract multiples of 10 from whole tens.

Bar modelling: subtract multiples of 10 from 2-digit numbers

Bar modelling: subtract from a 2-digit number (easier).

Bar modelling: subtract from a 2-digit number (harder)

Using images of base 10 blocks to help with subtraction.