Adding and Subtracting Within 1000
A 45-minute Grade 2 lesson extending the trade to a third column, including the case everybody dreads: subtracting from a number full of zeros.
Adding and Subtracting Within 1000 is a free 45-minute Grade 2 maths lesson plan for Common Core standard 2.NBT.B.7 — add and subtract numbers up to 1000. It is timed across 5 sections, gives the exact wording to use where the wording carries the mathematics, names 3 misconceptions with the teaching move that addresses each, and ends with an exit ticket and a printable worksheet with its answer key.
- Grade:
- Grade 2
- Length:
- 45 minutes
- Standard:
- 2.NBT.B.7
Grade 2 · Number & Operations in Base Ten
2.NBT.B.7
Add and subtract within 1000, using concrete models or drawings and strategies based on place value.
Objective
Students will be able to add and subtract three-digit numbers, regrouping between any two adjacent places.
Students are successful when they can
- Adds three-digit numbers with a trade in the ones, the tens, or both.
- Subtracts with a trade from the hundreds.
- Subtracts from a number with a zero in the tens place.
What you need
- Base ten materials including hundred flats
- Place value mats with three columns
- Calculation cards including several with zeros
- The printable practice sheet linked at the end of this plan
The lesson
Warm-up — where will the trade be?
5 min- Show four calculations and ask only where a trade will be needed — ones, tens, both, or neither.
- No answers yet. Predicting the trade is the planning step this lesson depends on.
Teach — the same trade, one column along
13 min- Build 356 + 278. Ones make fourteen: trade ten units for a rod. Tens now make thirteen: trade ten rods for a flat.
- Two trades in one calculation, each the same move one column along. Write it as you build it.
- Now 512 − 348. The ones need a trade from the tens; the tens then need one from the hundreds.
- Then the hard one: 400 − 176. The tens column has nothing to give.
- Trade a hundred flat for ten rods first, then a rod for ten units. Two trades before any subtracting happens.
- Say what the zeros meant: not 'nothing there', but 'nothing there yet — go further left'.
“A zero does not stop you. It means that column has nothing to lend, so you go one more place left and come back.”
Guided practice — build the hard ones
12 min- Pairs work through cards, building every subtraction that involves a zero.
- They say the trades out loud before performing them.
- Each answer is checked by adding back.
Independent practice
12 min- Students complete an adding and subtracting within 1000 page.
- Subtractions across a zero are the diagnostic items. Errors elsewhere are usually carelessness; errors there are conceptual.
Close
3 min- Give 300 − 145 and ask only what has to be traded, in order.
- A hundred for ten tens, then a ten for ten ones. Stop there.
What goes wrong, and why
Each of these is a reasoning error rather than carelessness. The fix addresses the reasoning.
Answers 400 − 176 by treating each zero column as giving a zero result.
Why: The column has nothing in it, so nothing seems available to work with, and zero is written as the honest answer for that column.
Fix: Build 400 as four flats and trade one flat down through the columns physically. The number is unchanged and now every column has something.
Trades in the ones but forgets the tens now needs one too.
Why: The trade has been learned as a single event rather than as something that can cascade. One trade felt like it completed the job.
Fix: Check each column in order and out loud after the previous trade is done. A trade changes the column above it, so that column has to be looked at again.
Adds 356 + 278 and writes 5124 by recording each column's total.
Why: Each column has been added correctly with no constraint on how many digits a column may hold.
Fix: The place value mat with a nine-per-column limit. The materials will not fit, so the trade happens before the writing does.
If they are not there yet
- Work with one trade at a time before any calculation needs two.
- Use the materials throughout. The written method for subtracting across zeros is meaningless without the trade it records.
If they finish early
- Subtract from 1000, which needs the trade to run through three columns.
- Add three three-digit numbers.
- Solve 623 − ___ = 178, which reverses the process.
Exit ticket
Work out 500 − 236.
What to look for: 264. An answer of 336 means each column was subtracted smaller-from-larger; an answer with a 0 in the tens means the zero column was treated as unable to lend.
Printable practice for 2.NBT.B.7
Free to print and copy, answer key included. Each sheet can generate a fresh set of problems for a retake.
- Add Within 1000 — No RegroupingWork out each answer.
- Add Within 1000 — With RegroupingWork out each answer.
Questions about Adding and Subtracting Within 1000
How long does the Adding and Subtracting Within 1000 lesson take?
45 minutes, split across 5 timed sections: warm-up 5 min, teach 13 min, guided practice 12 min, independent practice 12 min, close 3 min. The minutes are stated per section and add up to the stated length, so the plan can be cut or extended at a section boundary rather than abandoned halfway.
Which standard does Adding and Subtracting Within 1000 teach?
CCSS.MATH.CONTENT.2.NBT.B.7 — 2.NBT.B.7, Number & Operations in Base Ten for Grade 2: “Add and subtract within 1000, using concrete models or drawings and strategies based on place value.” In plain terms, add and subtract numbers up to 1000.
What do I need to teach this lesson?
Base ten materials including hundred flats, place value mats with three columns, calculation cards including several with zeros and the printable practice sheet linked at the end of this plan. Everything listed is either ordinary classroom equipment or a free printable from this site — there is nothing to buy and nothing to prepare beyond photocopying.
What mistakes should I expect in this lesson?
Three, each a reasoning error rather than carelessness: answers 400 − 176 by treating each zero column as giving a zero result; trades in the ones but forgets the tens now needs one too and adds 356 + 278 and writes 5124 by recording each column's total. The plan gives the thinking behind each one and the teaching move that addresses the thinking rather than the symptom.
How do I know whether the lesson worked?
The exit ticket asks: “Work out 500 − 236.” 264. An answer of 336 means each column was subtracted smaller-from-larger; an answer with a 0 in the tens means the zero column was treated as unable to lend. That tells you whether the class needs a reteach or a thirty-second conversation before you plan tomorrow.
Is there a worksheet to go with Adding and Subtracting Within 1000?
Yes — 2 printable 2.NBT.B.7 worksheets, linked at the end of the plan and free like the rest of the site. Each one comes with an answer key and 25 versions, so the practice after the lesson can be a different paper on every desk.
Is Adding and Subtracting Within 1000 free to use?
Yes. The plan, its printables and their answer keys are free to read, print and photocopy for your own class, with no account and no email capture. It was last reviewed on 5 September 2026. Please do not resell it or republish it as your own.
Last reviewed 2026-09-05. Aligned to 2.NBT.B.7 of the Common Core State Standards for mathematics.