RECOGNIZE AND CATEGORIZE SHAPES – Grade 4

Everyone wants to count triangles in this figure but what about rhombi, parallelograms and trapezoids? Hexagons and pentagons? Dodecagons anyone? The abundance of parallel lines make this a good figure for 4th graders to study, both as a review of some of the shapes addressed in previous grades and as an opportunity to classify quadrilaterals based on the presence of one or two sets of parallel lines.

2.G.A.1 – recognize triangles, quadrilaterals, pentagons and hexagons

3.G.A.1 – recognize rhombi as examples of quadrilaterals

4.G.A.2 – recognize parallelograms and trapezoids* by their attributes

**Investigate**

Q1: What shapes do you see?

Q2: How many of each shape are there? Count all same sized shapes as one shape. [For example, there are 4 different sized triangles.]

Q3: How would you organize each of these shapes into categories?

Q4: How many categories do the rhombi belong to? Make your case.

*Although students are composing trapezoids as early as grade 1, it’s not until grade 4 that students are considering its defining attributes. Use the inclusive definition of the trapezoid, a quadrilateral with *at least* one set of parallel sides.