3rd Grade · Math · 3.NBT.A.2
Subtraction Lesson Plan for 3rd Grade
A ready-to-teach subtraction lesson for 3rd Grade. Everything below is classroom-tested structure: an objective, a 45-minute sequence, a way to check who got it, and 6 printable practice pages.
Approximately 45 minutes
Learning objective
- Subtract a 1-digit number from a 2-digit number
- Apply basic regrouping when the ones digit is insufficient
- Build fluency with simple 2-digit subtraction problems
Materials
- Mental math (with borrowing): Subtracting 2-digit numbers - Finishline
- Subtract 1-digit from a 2-digit number
- Subtract 1-digit from a 2-digit number (missing number)
- Subtract whole tens from a 2-digit number
- Subtract whole tens from a 2-digit number (missing number)
- Subtract whole tens from a 3-digit number
- Pencils, and whiteboard space for the modeled examples
Lesson steps
1. Warm up together (5 min)
Open with a quick count-around or number talk that touches subtraction. Ask students where they have seen subtraction outside of math class. You are listening for who already has the vocabulary and who does not, so keep it light and let several students answer.
2. Model it (I do) (10 min)
Work two examples of subtraction on the board, thinking out loud the whole way. Say the quiet parts: what you notice first, which step you do next, and why. Deliberately make one small error on the second example and let the class catch it.
3. Practice together (we do) (10 min)
Work three more problems as a class. Ask a different student to supply each step rather than the whole answer. If a step stalls, drop back to concrete objects or a drawing before moving on.
4. Independent practice (you do) (15 min)
Hand out "Mental math (with borrowing): Subtracting 2-digit numbers - Finishline". Students work independently while you circulate. Note who is fluent, who is counting on fingers, and who has not started, because that grouping drives tomorrow's small group.
5. Close the loop (5 min)
Pull the class back. Ask one student to explain a problem they got right and one to name something that is still confusing. End on the confusion, not the success, so students learn that naming a gap is normal.
Check for understanding
Collect the practice pages and sort them into three piles: fluent, developing, and not yet. Any student in the third pile needs subtraction retaught in a small group before the class moves on.
Differentiation
Extra support. Students who stall: pull them into a small group and rebuild subtraction with concrete materials or a simpler text before asking for the written work again. Do not send the page home as homework, it will just rehearse the misunderstanding.
Extension. Students who finish early: ask them to write their own subtraction problem for a partner to solve, then check the partner's work. Creating a problem is harder than solving one and it surfaces whether they really understand subtraction.
Skills covered in this lesson
Subtract 1-digit from a 2-digit number · Subtract 1-digit number from a 2-digit number (missing number) · Subtract whole tens from a 2-digit number · Subtract whole tens from a 2-digit number (missing number) · Subtract whole tens from a 3-digit number · Subtract whole tens from a 3-digit number (missing number) · Subtract whole hundreds from a 3-digit number · Subtract a 2-digit number from whole hundreds · Subtract whole hundreds from whole hundreds · Subtract whole hundreds from 4-digit numbers · Subtract any whole ten number from 1,000 · Subtract a 3-digit number from any whole thousand
