Lesson Plan

Two-Step Back Jumps

Overview

In this lesson (lesson 5 of 7), students practise subtracting two- and three-digit numbers using an empty number line. They learn to work backwards and plan efficient “jumps” while explaining why different pathways can still reach the same answer.

Learning intentions

• Students will model subtraction on an empty number line for two- and three-digit numbers.
• Students will solve subtraction problems by working backwards and choosing efficient jump sizes (ones, tens, hundreds).
• Students will compare different strategies and explain how they know the answer is correct.
• Students will use precise maths language when describing their jumps and reasoning.

Success criteria

• I can show the start, jumps, and end on an empty number line for subtraction.
• I can choose a sensible jump strategy (ones/tens/hundreds) to reach the answer efficiently.
• I can explain my subtraction method and what each jump represents.
• I can check my answer by using an inverse strategy (addition) or a sensible estimation.

Curriculum links

• Number and place value: using place value to make sense of two- and three-digit subtraction strategies.
• Number and algebra: using efficient mental and written strategies for subtraction and explaining thinking.
• Measurement and geometry (as a support skill): using number lines as mathematical models for reasoning.
• General capabilities: Critical and Creative Thinking (strategise and compare), Personal and Social Capability (explain respectfully in a small group).

Lesson structure (45 minutes)

1. 5 min | Hook with number line

• Open with the introduction slides and show a subtraction situation like “Start at 86. What if we subtract 37?” Ask: “What would working backwards mean here?”
• Students turn-and-talk with a partner (or small group) to suggest whether they would jump left by tens first or by ones, and why.

2. 7 min | Teacher modelling: empty number line

• Use the introduction slides to model one worked example using an empty number line.
• Script the method clearly: mark the start, decide jump sizes, record the jumps, and land on the end. Explicitly model inverse checking: “If my answer is 49, does 49 + 37 get back to 86?”

3. 8 min | Guided practice: choose jump sizes

• Display two short subtraction prompts on the introduction slides (one two-digit, one three-digit). Students suggest the first jump (e.g., “Jump back 20, then 17” or “Jump back 30, then 6”).
• Teacher draws the empty number line with the class and records their chosen pathway, including “same answer, different jumps” discussion.

4. 15 min | Main task: pathways on worksheets

• Distribute the subtraction empty number line worksheet. Students work in a group of 4, rotating roles: Recorder (draws the jumps), Explainer (talks through steps), Checker (does inverse check), Materials/Timekeeper (keeps track and signals when to move).
• Students complete subtraction problems on empty number lines. Each student attempts at least one pathway fully, then one additional problem showing a second possible pathway (e.g., jump by tens then ones, or tens in a different order).
• Teacher circulates using prompts: “Where did you start?” “What does one jump mean?” “How do you know your end is correct?”

5. 5 min | Strategy share and compare

• Bring students back and return to the introduction slides for a “Compare pathways” slide.
• Ask: “How did your jumps differ but your answer match?” Capture two or three student explanations using sentence stems:
• “I jumped back … because …”
• “My strategy was different because … but the number line showed …”

6. 3 min | Quick check (individual)

• Students complete one mini question on the same worksheet (or a scrap page if needed): “Solve and check.”
• Teacher collects a few solutions quickly to identify misconceptions (wrong jump direction, skipping landings, no inverse check).

7. 2 min | Plenary: exit reflection

• Use the introduction slides to show an exit prompt: “Today I used ____ jumps to subtract ____.”
• Students answer verbally or with a short written sentence. Teacher notes whether students can explain both the pathway and the check.

Resources

• the introduction slides (about 10 slides: hook, modelling, guided practice, pathway compare, plenary prompt)
• the subtraction empty number line worksheet (two- and three-digit subtraction on empty number lines, include at least one “show another pathway” prompt)
• Whiteboard and markers (or interactive whiteboard)
• Printed mini number line strip (optional, for students who need extra scaffolding)
• Role cards for group work (Recorder, Explainer, Checker, Timekeeper)
• Coloured counters or base-ten blocks (optional for pre-teaching jump sizes)
• Student pencils, erasers, scrap paper for inverse checking
• Timer for role rotation

Assessment

• Observation during guided practice and worksheet work: can students correctly place jumps and land on the end?
• Evidence from inverse checking: do students use addition to confirm or give a sensible explanation?
• Exit reflection: can students name the jump strategy and describe why it works?

Differentiation

• Support (ADHD/Autism): provide a partially drawn empty number line on the first problem (start marked, key jump markers faint). Use role cards and short timed steps. Offer sentence stems for explanations.
• Support (skill gaps): allow use of base-ten blocks or counters to build confidence with tens/hundreds jump sizes, then transfer to the number line.
• Extension: challenge students to create and explain a second subtraction pathway that uses a different sequence of jumps but arrives at the same answer, including a brief comparison of efficiency.
• EAL: ensure teacher modelling is visual and consistent; use key language prompts (“start”, “jump back”, “land on”, “check by adding back”) and accept short spoken explanations.