Subtraction problems with numbers up to 10, each with one number missing, sometimes the answer and sometimes one of the numbers in the problem. Missing-number problems make children think about how the numbers relate, not just follow a routine.

For a missing number in a subtraction, children can turn it into an addition: 9 − __ = 4 becomes "4 and how many make 9?". With an answer key. Press "Generate new" for a different page every time, so the same sheet can be practised several days in a row.