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Subtraction Flash Cards (within 20): Free Printable
Free printable subtraction flash cards (within 20): 12 cards per page with answers on the back (double-sided) or upside down on the front. New cards every click.
Math flash cards
Print, cut along the dashed lines and practise. 12 cards per page.
− flash cards · page 1 · front
Answers · page 1 · back
− flash cards · page 2 · front
Answers · page 2 · back
✅ Last checked:
📚 Curriculum sources: Common Core Grade 1: Operations & Algebraic Thinking · Common Core Grade 3: Operations & Algebraic Thinking · National curriculum in England: mathematics
Our worksheets and games follow school curriculum standards (US Common Core and the national curriculum in England). Every answer key is worked out by the computer, not typed by hand.
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How to use flash cards
Make two piles: “know it” and “still learning”. Go through the cards; if your child answers quickly, the card goes on the “know it” pile. Practise the other pile again, and add a few new cards each day.
US Common Core expects addition and subtraction within 20 to be fluent by the end of Grade 2.
Short and often beats long and rare: 5 minutes a day works better than 30 minutes once a week.
Questions grown-ups ask
How do I print answers on the back?+
Print double-sided and choose “flip on long edge”. The answer pages are mirrored so each answer lands behind its question.
My printer can't print double-sided.+
Choose “Small, upside down” answers. The answer is printed upside down at the bottom of each card instead.