Teacher GuideWeek 23Lines, Angles & Symmetry — Teacher Guide
Monday: Points, Lines, Segments & Rays
1Warm-up
1. point, line segment, ray, line
2Learn Table
1. Student copies each figure — check endpoints/arrows drawn correctly
3Identify
1. ray, line segment, point, line, line segment
4Number Talk
1. Maya is wrong — a line goes on forever so it is longer; we just can't draw all of it
2. Ray: starts at one point, shines on forever; segment stops at both ends
5Challenge
1. Letter A: usually 3 segments; accept any correct construction, compare counts

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Tuesday: Right Angles
1Warm-up
1. T, F, T, F
2Learn
1. Point out square-corner mark □
3Estimate First
1. yes (90°), no (60°), no (110°), yes (90°) — praise honest estimates
4Right Angles in Shapes
1. Square: 4, Rectangle: 4, Triangle: 0 (this one), Circle: 0
5Two Ways
1. Any two: paper corner, book corner, folded circle, index card

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Wednesday: Lines of Symmetry
1Warm-up
1. Any 3 right angles: door, window, book, table corner...
2Learn
1. Emphasize FOLD test — both halves match exactly
3Draw Lines
1. Heart: 1, Square: 4, Triangle (equilateral): 3, Rectangle: 2, Arrow: 1
4Word Problems
1. Rosa's heart: 1 line of symmetry
2. Sister is right — a circle has endless lines of symmetry (every line through the center)
5Create Own
1. Fold test should show matching halves

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Thursday: Geometry in the Real World
1Warm-up
1. YES (heart), NO (letter F), YES (square)
2Word Problems
1. Line segment — it has two endpoints (the corners)
2. Two rectangles (cut through middles) OR two triangles (cut corner to corner)
3. Yes — that is exactly what a line of symmetry means
3Equal Shares
1. Halves: 1 cut through middle; Fourths: 2 cuts; Circle halves: 1 cut through center
4Number Talk
1. Same! 2 fourths = 1 half
2. Square has 4; two right triangles have 1 each = 2, so the square
5Create Own
1. Accept any problem using the week's vocabulary

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Friday: Review & Self-Check
1Warm-up
1. C, A, B, D
2Estimate First
1. Square: 4, Heart: 1, Rectangle: 2, Triangle: 3
3Mixed Review
1. ray, right, 4, 1
4Word Problems
1. A square
2. One vertical + one horizontal cut (cross pattern) makes 4 equal fourths; accept the two-diagonals X pattern too
5Self-Check
1. Accept student self-assessment and reflection