| Objectives | Students will be able to: (1) subtract members from a set using objects; (2) write subtraction sentences from take-away actions; (3) tell take-away stories with local flavour. |
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| Materials | Counters; story props (paper mangoes, birds, fish); the - and = sign cards; whiteboards. |
| Key vocabulary | take away, subtract, minus, left, how many remain |
| Engage (starter) | (10 min) The mango thief drama: 9 paper mangoes on the tree... a puppet "thief" sneaks away 3! "How many LEFT?" The class counts the survivors: 6. The - sign strides back onto the board. |
| Develop (main) | (35 min) 1. Concrete rounds: build a set, physically remove some, count the remainder, write the sentence (9 - 3 = 6) — five rounds with falling scaffolds. 2. Pairs perform story cards (fish swim off, birds fly away, buns get eaten) and record each as a sentence. 3. The zero surprise: 5 - 5... nothing left! And 6 - 0... nothing taken! Both ends of subtraction met with laughter. 4. Invent-a-theft: pairs write one take-away story of their own with its sentence. |
| Plenary (close) | (10 min) Whiteboard theatre: teacher acts two silent take-aways with counters; children write both sentences from watching alone. |
| Assessment | Story sentences: 4 of 5 written correctly from actions; the zero cases answered; own story sentence matches its plot. |
| Teacher notes | Term 1 Week 7 planted the minus sign; today it grows roots. Insist the physical remove-and-count precedes every written sentence this week — subtraction rushed to symbols breeds the classic "count everything" errors. |
| Objectives | Students will be able to: (1) derive subtraction facts within 10 from known part-part-whole partitions; (2) recall subtraction facts with growing speed; (3) connect each subtraction fact to its addition partner. |
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| Materials | Part-part-whole mats from Term 1; counters; fact-family triangle cards; personal fact cards; the doubles ladder and make-ten wall in view. |
| Key vocabulary | fact, parts, whole, related, family |
| Engage (starter) | (10 min) The old friend reveal: hold a Term 1 partition mat — whole 7, parts 4 and 3. "You built this in October! Watch: 7 take away 4 leaves... the OTHER PART." Subtraction was hiding inside all along. |
| Develop (main) | (35 min) 1. Mat magic: build a whole, cover one part with a cup — the visible part answers the subtraction (7 - 4 = 3, no counting-back needed). Six rounds. 2. Triangle cards: whole on top, parts below — thumb covers any corner, say the hidden number (one card yields FOUR facts: 4+3, 3+4, 7-3, 7-4 — a whole family!). 3. Make-ten dividends: 10 - 6? The friends-of-ten wall already knows: 4! Harvest all six ten-subtractions free of charge. 4. Personal cards updated with first subtraction ticks. |
| Plenary (close) | (10 min) Cup game finale: whole of 8 built, part hidden, class calls the missing part — five rounds at rising speed. |
| Assessment | Triangle work: states 3 of 4 hidden corners correctly; one fact family (all four facts) recited from a single card; ten-subtractions answered from the wall. |
| Teacher notes | This is the payoff lesson for October's partition investment — subtraction as "the other part" beats counting-back for both speed and understanding. The triangle cards join the permanent kit. |
| Objectives | Students will be able to: (1) subtract by counting back 1, 2 or 3 on the number line; (2) choose between counting back and the parts method sensibly; (3) solve mixed subtraction facts within 10. |
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| Materials | Floor number line; personal number lines; fact cards sorted small-jump (9-2) and part-friendly (7-4); frog or counter to hop. |
| Key vocabulary | count back, hop, choose, strategy |
| Engage (starter) | (10 min) The frog on 9 must give back 2: hop... hop... lands on 7! "Counting BACK — walking the line in reverse." (November's backwards counting was training for this all along.) |
| Develop (main) | (35 min) 1. Line practice: subtract 1, 2, 3 by hopping backwards, fingers tracking hops — small jumps only. 2. The strategy fork taught honestly: 9 - 2 loves counting back (tiny hop); 9 - 6 hates it (six wobbly hops!) but loves the parts method (6 and WHAT make 9?). 3. Weapon-choice sort: pairs sort ten fact cards into "hop it" and "parts it" piles, then solve their pile. 4. Mixed gauntlet on whiteboards: six facts, free strategy choice, answers flashed. |
| Plenary (close) | (10 min) Strategy interviews: three volunteers reveal which weapon they chose for 8 - 3 and WHY. All sound choices honoured — mathematicians choose tools, not rules. |
| Assessment | Gauntlet: 5 of 6 correct; sort shows sensible strategy matching on most cards; one strategy choice justified aloud. |
| Teacher notes | Counting back beyond 3 hops collapses under working-memory load — teach its LIMIT as honestly as its use. Strategy CHOICE is the true objective; fluency follows it. |
| Objectives | Students will be able to: (1) estimate quantities before counting; (2) refine estimates using benchmark groups of ten; (3) check estimates by organised counting. |
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| Materials | Clear jars/cups with counters, seeds, buttons (20-60 range); a labelled benchmark jar of exactly 10; estimate slips; the grand-count grouping habit. |
| Key vocabulary | estimate, about, benchmark, too high, too low, check |
| Engage (starter) | (10 min) The mystery jar held high: "HOW MANY seeds? No counting — your eyes only!" Estimates slip into the box; the spread read aloud (from 15 to 100!) — "today we sharpen those eyes." |
| Develop (main) | (35 min) 1. The benchmark secret: beside the mystery jar, the TEN jar. "Does the mystery look like two tens? Four?" Estimates instantly improve — comparing beats guessing. 2. Estimation circuit: four stations, each with a mystery container and the ten-benchmark; pairs record estimates. 3. THE COUNT: containers emptied and counted in GROUPS OF TEN (January's habit) — truth revealed, estimates scored by closeness bands. 4. Round two on fresh jars: measurably sharper eyes, and the children feel it. |
| Plenary (close) | (10 min) Estimation wisdom circle: what made round two better? (The ten-jar! Grouping! Practice!) The mystery jar becomes a weekly classroom fixture. |
| Assessment | Station slips: round-two estimates closer than round-one for most; counting done in tens unprompted; benchmark comparison articulated. |
| Teacher notes | Estimation is number sense made visible — and it calibrates only through the estimate-then-verify loop. The weekly mystery jar costs two minutes and pays compound interest all year. |
| Objectives | Students will be able to: (1) demonstrate subtraction with sets, facts via parts and counting back, and quantity estimation (consolidation); (2) complete the week checkpoint. |
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| Materials | All week's kits; triangle cards; the mystery jar; checklist. |
| Key vocabulary | All week vocabulary |
| Engage (starter) | (10 min) Warm-up: one silent take-away theatre round; cup-game whole-of-9; a fresh mystery jar estimate. |
| Develop (main) | (35 min) Round-up circuit with checklist: Table 1: act and write two take-away sentences. Table 2: triangle cards — four hidden corners; recite one full fact family. Table 3: mixed six-fact gauntlet with free strategy; one strategy explained. Table 4: estimate a jar with the ten-benchmark, then group-count to check. Teacher records the week's key data: subtraction facts secure /10. |
| Plenary (close) | (10 min) Fact-family fanfare: the class chants one family in four voices. Preview: "Next week the BIG question: is this story a PLUS or a MINUS? Real mathematicians decide... and we pour a LITRE!" |
| Assessment | Week 9 checkpoint: take-away sentences from action; parts-method facts; count-back small jumps; estimation with benchmark. Subtraction /10 sample recorded. |
| Teacher notes | Compare each child's subtraction sample with their Week 10 T1 addition sample — subtraction typically trails addition by a few facts; a LARGE gap flags a child leaning on counting-all and needing mat time. |