Area of Triangles, Parallelograms & Trapezoids: Middle School Geometry
- Year groups
- Years 6–8
- Pages
- 5
- File type
- Preparation
- Print ready
- Subject
- Maths, Geometry, Measurements
- Topic
- Jigsaw, Hands-On Maths
- Resource types
- Teacher Tools
- Preparation
- Print ready
From the author
About this resource
Using the JIGSAW grouping strategy, your students can master the geometric formulas for the area of triangles, parallelograms, and trapezoids.
Jigsaw is a great way to encourage your students to work collaboratively and take control of their own learning. Students become experts at one skill, teach it to others, and also learn from their peers. This lesson uses the jigsaw strategy and an inquiry approach to help students understand the explanation for three area formulae.
Teacher Instructions:
Print two-page handouts (a third with each page 1, and all with the same page 2).
Split your class into three groups.
Each group is asked to master finding the area of one shape.
Students collaborate, using the grid, to prove/explain the formula.
THEN JIGSAW: Make trios with one expert from each group.
The three students teach each other about each formula.
This is a great lesson to reinforce the learning in a geometry unit, or it could be used an initial inquiry before you teach the formulas.
Grades to Use With:
This lesson is specifically designed for students in grade 6 and meets the following standard:
Common Core Standard: 6th Grade Geometry: Find the area of triangles and special quadrilaterals
British Columbia, Canada: Learning Standard Grade 6 Math: Determine the Area of Triangles, Parallelograms, and Trapezoids
However, it could also work with slightly older or younger students depending on split classes or your area's learning standards.
What's Included: 5-Page PDF: Ready to Print and Use
Title Page/Teacher Instructions
3 Unique Worksheets: One for each JIGSAW Group
A final worksheet you give to every student
If you enjoy this Grade 6 Math Lesson, check out some others from my store: Grace Under Pressure
6th Grade Math: Statistics and Probability
Nutrition Label Math: Real-World Percentages
Middle School Math Stations for Place Value
In the classroom
Teaching tips & learning objectives
Learning objectives
- Derive and explain the area formula for a triangle (b x h / 2) using a grid model
- Derive and explain the area formula for a parallelogram (b x h) using a grid model
- Derive and explain the area formula for a trapezoid ((a + b) / 2 x h) using a grid model
- Teach a peer-derived formula accurately after hearing it explained by a classmate expert
Teaching tips
- Print the two-page handout in triplicate, since a third of the class gets each shape as the teacher instructions specify
- Have expert groups finish the grid-based proof before starting the jigsaw rotation, so every trio receives a fully worked explanation
- Circulate during the trio phase to confirm all three formulas make it onto every student's sheet, since accuracy depends entirely on peer explanation
Skills covered
- Area of 2D shapes
- Geometry
- Cooperative learning
Good to know
Questions teachers ask about this resource
Is the second handout page the same for all three groups, or unique to each shape?
The same for all groups — the teacher instructions specify printing each group's unique page 1 with a shared page 2.
No reviews yet
Downloaded this resource? Tell other teachers how it went.
Resource details
Concepts & topics
Core concepts
Core concepts
- Area of a triangle
- Area of a parallelogram
- Area of a trapezoid
Topics