Flash cards for facts to 20, with the answers on the back

We keep a rubber band of flash cards in the car. Red light, three cards. The ones my kindergartner gets right go to the back, the ones she misses go behind the sun visor for tomorrow. The whole deck is facts within 10, horizontal, large, and it has lasted a year.

What the sheet looks like

The addition and subtraction flash cards generator prints a deck from the facts you choose: addition, subtraction, mixed, or fact-family triangle cards. Facts can be within 10, within 20, doubles (0 + 0 to 10 + 10), make ten pairs, or a single family such as +3 or −7. Cards print horizontal (7 + 5 =) or vertical, stacked, in large (4 per page), medium (6) or small (9), shuffled or in order, with dashed cut guides.

The answers option is where it earns its keep: a matching answer sheet for the grown-up, or two-sided answer backs, mirrored so that when you print double-sided each answer lands behind its own card.

Why it works

• One fact family at a time (+3, then +4) is how facts get learned, and a deck of only the +3 cards is 11 cards, which is a two-minute session.
• Make ten pairs (6 + 4, 7 + 3) are the most useful eleven facts in early arithmetic, and getting them automatic makes everything past 10 easier.
• The triangle cards show 3, 4 and 7 at the corners with no operation sign. Covering one corner and asking for it is addition and subtraction at once.

Who it suits

Kindergarten through second grade. Within 10 and doubles are kindergarten and first grade; within 20 and the subtraction families are the second-grade deck, and the triangle cards suit a child who has done both operations and keeps treating them as unrelated. The number bonds sheet is the step before flash cards for a child still counting on fingers, and the multiplication flash cards are the same format for third grade.

Small cards, nine to a page, are the size for a pocket. Large ones are for across a table.