This book contains practice worksheets for subtraction. It starts with single-digit calculations (1 − 1, 2 − 1, 3 − 2, ...) and works up in size and difficulty until the last pages are four-digit calculations with regrouping (also called borrowing). The levels are in the order they are usually taught. Single-digit calculations come first, then two-digit calculations that do not need regrouping, then calculations that do, and then the mixed ones where the child has to spot the regrouping themselves. Every level comes with five worksheets, one for each day of the school week.Chapters:1-9 By 1-51-9 By 1-92 Digit By 1 Digit Subtraction Without Regrouping2 Digit By 1 Digit Subtraction With Regrouping2 Digit By 1 Digit Subtraction With & Without Regrouping2 Digit By 2 Digit Subtraction Without Regrouping2 Digit By 2 Digit Subtraction With Regrouping2 Digit By 2 Digit Subtraction With & Without Regrouping3 Digit By 2 Digit Subtraction With & Without Regrouping3 Digit By 3 Digit Subtraction With & Without Regrouping4 Digit By 3 Digit Subtraction With & Without Regrouping4 Digit By 4 Digit Subtraction With & Without Regrouping