Use a fact you know to reach one you don't: 8 + 7 is a double plus one, 9 + 5 is 10 + 4. For subtraction, think addition: 13 − 6 asks what adds to 6 to make 13.
facta short sum or difference you know by heart
doublea number added to itself: 6 + 6
make a tenfill up to 10 first: 8 + 5 = 10 + 3
fluentlyquickly and correctly
Watch for: Counting on fingers from 1 every time instead of using a known fact. Answers off by one: 8 + 7 = 14 or 13 − 6 = 8. Adding when the sign is −, in a mixed row.
At home: Play a quick card game: flip two cards and say the sum. A few minutes a day works better than one long session.
Sample sheet and answer key
Freddie's Frog Pond
Grade 2 · Facts within 20 · 2.OA.B.2
NameDate
Freddie the frog lives in a busy pond full of bugs, lily pads and friends. Solve each problem to help Freddie out!
Beat the clock
How many can you do in three minutes? Then finish the rest.
New problems every time, three levels (gentle, core and stretch), themes to pick from, a second page if you want one. Each sheet comes with an answer key and a one-page guide for grown-ups.
