Virginia SOL 2.MG.3

2.MG.3 is a Standards of Learning standard. These are the knowledge and skills expectations under it.

• 2.MG.3.a

  Explore a figure using a variety of tools (e.g., paper folding, geoboards, drawings) to show and justify a line of symmetry, if one exists.

• 2.MG.3.b

  Create figures with at least one line of symmetry using various concrete and pictorial representations.

• 2.MG.3.c

  Describe the two resulting figures formed by a line of symmetry as being congruent (having the same shape and size).

01

What Students Need to Do

Students identify shapes that can be split into matching halves. They test, draw, and create lines of symmetry, then explain that the two halves are congruent.

02

What Mastery Looks Like

Students can find and test lines of symmetry by folding, drawing, or using a geoboard. They can create a symmetric figure and explain that its matching halves have the same shape and size.

03

Common Misconceptions

Students may think any line that cuts a shape into two parts is a line of symmetry. They may also think congruent means the same shape but not necessarily the same size.

04

How to Assess It

Give students a rectangle and a scalene triangle. Ask them to draw any lines of symmetry, then explain why the resulting parts are or are not congruent.

1. 01

   Give students paper shape cutouts to fold, then have them trace each crease that makes two matching halves.

2. 02

   Ask students to explain in writing: How does folding a shape prove that its two halves are congruent?

3. 03

   Play a card sort where students group shapes by number of symmetry lines, then check each choice with a small mirror.

4. 04

   Search the classroom for symmetric objects, sketch one, and mark where a line of symmetry would go.

• 2.MG.4

  The student will describe, name, compare, and contrast plane and solid figures (circles/spheres, squares/cubes, and rectangles/rectangular prisms). 

• K.MG.2

  The student will identify, describe, name, compare, and construct plane figures (circles, triangles, squares, and rectangles).

• 4.MG.6

  The student will identify, describe, compare, and contrast plane and solid figures according to their characteristics (number of angles, vertices, edges, and th...

• 1.MG.2

  The student will describe, sort, draw, and name plane figures (circles, triangles, squares, and rectangles), and compose larger plane figures by combining simpl...