Unit Plan 36 (Grade 2 Math): Cumulative Synthesis & Exhibition

Focus: Show what you know with integrated tasks blending OA, NBT, MD, and G; students present and defend reasoning with clear models, units, and explanations.

Grade Level: 2

Subject Area: Mathematics (Comprehensive Spiral)

Total Unit Duration: 5 sessions (one week), 45–60 minutes per session

I. Introduction

Students apply the year’s learning to authentic, multi-step problems that cut across operations & algebraic thinking, number & place value, measurement & data, and geometry. Teams design solutions, justify methods, and exhibit their work to peers.

Essential Questions

• How do I choose the most efficient strategy for a problem?
• What counts as evidence when defending a mathematical decision?
• How do representations (drawings, number lines, tables/graphs, models) make my argument clear?

II. Objectives and Standards

Learning Objectives — Students will be able to:

1. Tackle multi-step problems requiring combined skills from 2.OA, 2.NBT, 2.MD, 2.G.
2. Select and justify efficient strategies (e.g., tens/ones reasoning, open number line, bar model).
3. Use representations (drawings, number lines, tables, bar graphs/line plots, shape diagrams) to support claims.
4. Communicate with precision: correct units/labels, clear numbers/symbols, and reasonableness checks.
5. Present and defend solutions using math vocabulary; respond to questions and feedback.

Standards Alignment — CCSS Grade 2 (spiral across the unit)

• 2.OA: One-/two-step word problems; add/sub within 20; arrays/odd-even ideas as needed.
• 2.NBT: Place value; add/sub within 100 & 1,000; mental 10s/100s; explain strategies.
• 2.MD: Measure/estimate lengths; add/sub lengths on number lines; time & money; make/interpret data displays.
• 2.G: Recognize/draw/classify shapes using attributes; partition shapes into equal shares.
• Mathematical Practices (MP.1–MP.8) threaded throughout.

Success Criteria — Student Language

• I can plan a multi-step solution, show models, and explain why it works.
• I can keep units/labels accurate and check if my answer makes sense.
• I can present my thinking and answer questions using math words and evidence.

III. Materials and Resources

Tasks & Tools (teacher acquires/curates)

• Mixed project cards (e.g., class picnic planning, school store, playground map, poster design with shapes).
• Math journals; base-ten blocks; place-value charts; rulers; number lines; clock faces; coin mats/price lists.
• Graph templates (tally tables, bar graphs, line plots with whole units).
• Large chart paper or exhibition boards, markers, glue/tape.
• Feedback rubrics and TAG (Tell–Ask–Give) peer-review slips.

Preparation

• Anchor charts: Choose a Strategy, Units & Labels, Show Your Thinking, Defend Your Claim.
• Sentence stems: “I chose __ because __.” “My model shows __.” “A possible error is __; we checked by __.”

Common Misconceptions to Surface

• Dropping units/labels ($, cm, minutes).
• Mixing time and length models; misreading scales.
• Regrouping mistakes (tens/ones) or misplacing digits.
• Classifying shapes without citing attributes.

Key Terms (highlighted in lessons) strategy, representation, equation, unknown, tens/ones/hundreds, regroup, unit/label, length, time interval, coin value, graph, data, attribute, triangle, quadrilateral, partition, claim, evidence, reasonableness

IV. Lesson Procedure

(Each day: Launch → Explore → Discuss/Consolidate → Reflect. Suggested timing for a 45–60 min block.)

Session 1 — Capstone Launch: Plan Your Approach (OA, NBT; MP.1, MP.4)

• Launch (8–10 min): Introduce a rich scenario (e.g., snack-pack planning with prices, quantities, and length limits for packaging).
• Explore (15–20 min): Teams identify sub-problems and map a plan (What will we measure? Where do we use tens/ones? What needs a graph?).
• Discuss (8–10 min): Share planning choices; highlight multiple valid paths.
• Reflect (3–5 min): Write your solution plan (operations, representations, and a reasonableness check).

Session 2 — Measures & Data: Models That Communicate (MD; MP.5, MP.6)

• Launch (5–7 min): Mini-lesson: choosing displays—bar graph vs. line plot; when to use a number line.
• Explore (20–22 min): Build one data display (measure lengths or prices/quantities) and label with units and readable scales.
• Discuss (10–12 min): Evaluate clarity: titles, labels, units, scale choice.
• Reflect (3–5 min): One improvement to your representation and why.

Session 3 — NBT Decisions: Efficient and Accurate (NBT; MP.2, MP.7)

• Launch (8–10 min): Compare two approaches: open number line vs. place-value method; which is more efficient and why?
• Explore (15–20 min): Compute critical subtotals both ways when sensible; document the chosen method and rationale.
• Discuss (8–10 min): Share where regrouping or mental 10s/100s saved time.
• Reflect (3–5 min): “We chose __ because __.”

Session 4 — Build the Argument: Write, Check, Anticipate (All strands; MP.3, MP.6)

• Launch (5–7 min): Model a short defense paragraph: claim → evidence (work + model) → units → reasonableness.
• Explore (18–22 min): Teams draft their argument; add a counterexample or “skeptic’s question.”
• Discuss (10–12 min): Peer micro–Q&A: partners ask focused questions; teams tighten explanations.
• Reflect (3–5 min): Note one anticipated question and your prepared response.

Session 5 — Exhibition: Present, Question, Revise (All strands; MP.1–MP.8)

• Task (25–30 min): Present solution boards (problem statement; plan; work with units; data/graph; model like number line/shape diagram; final conclusion; reasonableness).
• Peer Review (TAG, 5–7 min):
  • Tell a strength (clarity of model/units).
  • Ask a focused question (method choice, rounding, or representation).
  • Give a concrete suggestion (tighten labels or explanation).
• Reflect (5–7 min): “We revised __ because __.”

V. Differentiation and Accommodations

Advanced Learners

• Add constraints (budget cap, dimension limit) and optimize; compare two near-optimal solutions and defend the better choice.
• Require two distinct representations that lead to the same answer; discuss pros/cons.

Targeted Support

• Provide checklists (units present, labels, estimate, computation, check).
• Scaffolded tables/frames (place-value frames, partially labeled number lines, pre-made graph axes).
• Use smaller numbers to focus on reasoning and units.

Multilingual Learners

• Visual sentence frames: “Our claim is __ because __.” “The graph/model shows __.” “We rounded because __.”
• Word/visual glossary for key terms; partner rehearsal before presenting.

IEP/504 & Accessibility

• Option for oral presentation with a partner scribe; large-format graph/coordinate paper.
• Chunk the task into milestones with quick checks; provide manipulatives (base-ten blocks, clocks, coin kits).

VI. Assessment and Evaluation

Formative Checks (daily)

• S1: Coherent plan with sub-problems identified and chosen representations.
• S2: Accurate, well-labeled data displays with correct units/scales.
• S3: Appropriate method choice (place value, number line) and correct computations.
• S4: Clear written argument with a reasonableness check.
• S5: Effective presentation and responsive Q&A.

Summative (end of week; 0–2 per criterion, total 10)

1. Mathematical Accuracy (OA, NBT, MD, G)

• 2: Correct computations, conversions, and models.
• 1: Minor errors that don’t change the conclusion.
• 0: Major errors or unsupported results.

2. Strategy & Representation (MP.4, MP.5, MP.7)

• 2: Efficient strategy; representations fit the purpose and are well-labeled.
• 1: Mostly sound strategy; minor labeling issues.
• 0: Inefficient or mismatched representation.

3. Reasoning & Communication (MP.2, MP.3)

• 2: Clear claim with evidence; anticipates a question/counterexample.
• 1: Partially justified or vague in places.
• 0: Assertions without support.

4. Precision with Units/Labels (MP.6)

• 2: Units, rounding, and symbols are precise; work is readable.
• 1: Minor precision lapses.
• 0: Disorganized or imprecise.

5. Collaboration & Presentation (MP.1, MP.8)

• 2: Equitable teamwork; addresses feedback thoughtfully; presentation clear.
• 1: Uneven participation or limited revisions.
• 0: Minimal collaboration or dismisses feedback.

Feedback Protocol (Exhibition)

• Read & Restate (1 min): Reviewer restates the team’s claim and goal.
• TAG (2–3 min): Tell a strength; Ask a focused question; Give a suggestion.
• Evidence Check (1 min): Point to a representation or calculation that supports—or challenges—the claim.
• Author Response (1–2 min): Team records one revision and why it improves the solution.

VII. Reflection and Extension

Reflection Prompts

• Where did your estimate catch a possible error?
• If you had one more day, what representation or unit check would you add and why?
• Which math practice helped your team the most?

Extensions

• Alternate Scenario: Rework your solution under a new constraint (budget/time change; size limit).
• Two-Method Proof: Solve a core step two ways (place value vs. number line) and compare.
• Community Share: Turn your exhibition board into a hallway display with quick QR audio explanations.

Standards Trace — When Each Strand Is Addressed

• 2.OA — Sessions 1, 5
• 2.NBT — Sessions 1, 3, 5
• 2.MD — Sessions 2, 5
• 2.G — Sessions 4, 5
• MP.1–MP.8 — All sessions (perseverance, reasoning, argument, modeling, tools, precision, structure, regularity)