2.1 The difference between minus and negative
2.2 Subtraction as shorthand notation
2.2b TASK: Subtraction as a shorthand notation
2.3 A scaffold for subtraction
2.3b A scaffold for subtraction
2.4 TASK: Subtraction — Some to try
2.5 Variation — Match up the calculations
2.5b TASK: Variation — Match up the calculations
2.6 TASK: Equivalent Subtractions and Additions
2.7 TASK: Efficient mental methods
2.8 TASK: Generalising subtraction
2.9 TASK: The two 2's challenge
2.10 A flawed model for subtraction
2.10b A flawed model for subtraction