Unit 10: 2 Dimensional Shapes

Below you will find an overview of the concepts that your child has learned throughout unit 10! This geometry unit has a lot of vocabulary. I would suggest reviewing the vocabulary with your child.

Lines, Rays, Line Segments, Angles

Types of Angles

First students learned about right angles and we discussed how you can use right angles to determine the other types of angles. A right angle is an angle with a square corner. (Students will learn about angle degrees in the next unit) Once students had an understanding of right angles, they learned that an acute angle is smaller than a right angle. To help students remember the definition of acute angles I told them to think of a "cute little baby" to help them remember that an acute angle is an angle that is smaller than a right angle. For obtuse angles, I told them to think of a "big sneeze"' We would go " ob..ob...tuse!" in a sneezing sound. It was quite funny!   Then students did an angle sort. They were given a right angle on wax paper and they got to measure and explore angles using their right angle. So, if the angle was less than a right angle it was acute. If it was greater than a right angle it was obtuse. Please see below for pictures of students measuring their angles!

This is an acute angle because it is smaller than a right angle.

This angle is obtuse because it is greater than a right angle.

Here's an example of their finished angle sort.

Classifying Triangles

Next students learned how to classify triangles by sides and angles. See anchor charts below. Students had a lot of hands on practice classifying triangles. 

Types of Lines

Next students learned about the different types of lines. 

Students enjoyed finding the different types of lines in a map. 

Classifying Quadrilaterals

Next we classified quadrilaterals. Students learned that the same quadrilateral can have different names. For example, a square is a parallelogram, a rhombus, and rectangle. 

Lines of Symmetry 

We also discussed that just because a shape has a line that splits the shape in half, it doesn't always mean that it is a line of symmetry. In order for it to be a line of symmetry, you should be able to fold that shape over the line so that the 2 parts would match exactly.

For example, in this problem Jackie is correct. Please have your child explain to you why!