Add or subtract like places: ones with ones, tens with tens, hundreds with hundreds. Start with the ones and regroup a ten or a hundred when a column needs it.
hundredsgroups of one hundred
place valuewhat a digit is worth from where it sits
regrouptrade 10 ones for a ten, or 10 tens for a hundred
sumthe answer to +
Watch for: Digits drifting into the wrong column. Forgetting the ten carried into the hundreds when the tens add to 10 or more. Subtracting the smaller digit from the bigger one in every column.
At home: Use play money or paper slips for $100, $10 and $1 to act out a sum. Trading ten $10 slips for one $100 shows regrouping.
Sample sheet and answer key
Freddie's Frog Pond
Grade 2 · Adding and subtracting within 1000 · 2.NBT.B.7
NameDate
Freddie the frog lives in a busy pond full of bugs, lily pads and friends. Solve each problem to help Freddie out!
Warm-up: hundreds
Hundreds add like ones do.
300 + 500 =800 − 100 =400 + 300 =700 − 100 =
Adding
Ones, then tens, then hundreds.
1
851+139
2
366+617
3
317+606
4
331+366
5
690+150
Subtracting
Trade a ten or a hundred when a column is short.
1
682−420
2
666−302
3
872−508
4
120−116
5
312−116
Story time
1
Moss has 852 water bugs. Freddie has 636. How many more water bugs does Moss have than Freddie?
water bugs
2
Fern has 156 pebbles. Pip gives Fern 376 more. How many pebbles does Fern have now?
pebbles
Sheet
Freddie's Frog Pond
Grade 2 · Adding and subtracting within 1000 · 2.NBT.B.7
Answer key
Freddie the frog lives in a busy pond full of bugs, lily pads and friends. Solve each problem to help Freddie out!
Moss has 852 water bugs. Freddie has 636. How many more water bugs does Moss have than Freddie?
852 − 636 = 216
216water bugs
2
Fern has 156 pebbles. Pip gives Fern 376 more. How many pebbles does Fern have now?
156 + 376 = 532
532pebbles
Answer key
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.
