Grade 3 Geometry Complete Unit | 12 Lessons | 3.G

A complete 14-day Grade 3 unit covering all of CCSS 3.G — classifying 2D shapes by attributes and partitioning shapes into equal fractional parts.

This is the unit where students learn the language of geometry: sides, vertices, angles, polygons, triangles, quadrilaterals, special quadrilaterals (squares, rectangles, rhombuses), and the other polygons (pentagons, hexagons, octagons). Then students move into partitioning — splitting shapes into halves, thirds, fourths, and beyond — and naming each equal part as a unit fraction. Built by a classroom teacher who knows that the jump from “shapes have names” to “squares are special rectangles” is one of the biggest concept jumps in Grade 3 math.

Twelve fully-scripted lessons walk students through: 2D shape vocabulary, polygons vs non-polygons, triangles, quadrilaterals, special quadrilaterals (square/rectangle/rhombus), other polygons (pentagons, hexagons, octagons), shared attributes (the key 3.G.A.1 idea), and partitioning into halves, thirds, fourths, and beyond, equal areas vs unequal partitions, with a final synthesis lesson — culminating in a “Quilt Patterns” performance task where Mia designs quilt patches and students apply EVERY 3.G skill: naming shapes by attributes, recognizing shared attributes (a square is also a rectangle), and partitioning patches into equal fractional parts.

What’s included:

• 12 lesson decks (120 slides) — fully scripted with speaker notes
• 12 worksheets (8 practice + 1 word problem + 2 bonus per lesson) + answer keys with misconception notes
• 12 exit tickets (3 questions, ~5 minutes) + answer keys with reteach suggestions
• Pre/Post Assessment — 10 questions mapped to every 3.G sub-standard
• Summative Performance Task — “Quilt Patterns” (5 parts, 16 points)
• Problem-Solving Rubric — 4 criteria × 4 levels
• 4 Anchor Charts — wall posters for shape vocabulary, naming polygons, special quadrilaterals, and equal partitions
• 14-Day Pacing Guide
• Parent Letter (editable)

Lesson sequence:

• Lesson 1. 2D Shape Vocabulary (3.G.A.1)
• Lesson 2. Polygons vs Non-Polygons (3.G.A.1)
• Lesson 3. Triangles (3.G.A.1)
• Lesson 4. Quadrilaterals: The Big Family (3.G.A.1)
• Lesson 5. Special Quadrilaterals (3.G.A.1)
• Lesson 6. Other Polygons (3.G.A.1)
• Lesson 7. Shared Attributes (3.G.A.1)
• Lesson 8. Partitioning: Halves (3.G.A.2)
• Lesson 9. Partitioning: Thirds and Fourths (3.G.A.2)
• Lesson 10. Equal Areas, Unit Fractions (3.G.A.2)
• Lesson 11. Non-Equal Partitions (3.G.A.2)
• Lesson 12. Real-World 3.G Synthesis (3.G all)

Standards: 3.G.A.1 — Understand that shapes in different categories may share attributes (e.g., quadrilaterals). Classify shapes by attributes. 3.G.A.2 — Partition shapes into parts with equal areas. Express each part as a unit fraction of the whole.