Introducing 3D Shapes

The week before Spring Break marked my Grade 8's introduction to 3D Shapes.

This is our 6th unit of the 8 that we will cover this year and, personally,

I think it is one of the most fun!

Here are some of the activities we completed over the week,

they were NOT all done in one day.

PRIMARY ACTIVATION

     I started off the unit by having students, in groups of 4, brainstorm ALL of the ingredients they would need if they were going to bake a cake. Some students went very simple with the boxed-cake-mix approach, others had detailed lists for baking one from scratch, and others were much more focused on the decorating options!

     When completed, I asked my students the following questions:

What is the shape of the container that that ingredient comes in?

Does the shape of the container match the shape of the ingredient?

What things do companies keep in mind when selecting package shapes?

I was really pleased with the responses of the last question, which ranged from convenience and usable marketing space to environmental sustainability and purpose.

     I then presented my students with the two images below and asked them, "If both golf balls and tennis balls are spheres, then why does one often come packaged in rectangular prisms while the other often comes packaged in cylinders?"



Again, my students had excellent ideas and one student quickly pointed out that, "I lose WAY more golf balls than tennis balls so when I buy lots of boxes they stack in my garage!"

     We then revisited the concept of a 2D Net for a 3D Shape, a concept they were introduced to in elementary school. We discussed how a net is a pattern for a 3D shape and, while some nets include small tabs to help them glue easier, a net does not have any overlaps or gaps. They were then presented with the image below which depicts the 11 different nets that can form a cube. I then asked my students:

What 3D shape can be formed by these nets?

Does each net form the shape successfully?

How do you know?

     I then put together 6 centers/stations that my students worked through over the course of 2-3 classes. We do centers/stations almost every time we have a new concept and my students respond really well to them, plus it gives me a great chance to focus on small-group formative assessment.

Station 1

- Concentration/Memory Match Game

     - Students were tasked with matching 3D shapes to their

        respective nets

Station 2

- Crazy Nets

     - Students were provided with complex nets that would create

        3D shapes like icosahedrons (soccer balls) and hebdomicontadissadron

        (the Death Star from Star Wars)

     - Find complex nets here

Station 3

- Conference with Me

     - I always build in one center/station that allows me to sit down

       with students and complete formative assessments for the topic

Station 4

- Computer Activities

     - Students were provided with three different computer activities/

        games to explore through

     - 3D Shapes from BBC KS2 Bitesize Maths

              - Short introductory information interactive

              - Good for students who need to review information first

     - Play Nets

              - Answer various questions and challenges about nets &

                 3D shapes

              - Various levels of difficulty and teachers can track progress

     - Mission 2110 Roboidz: 3D Shapes

              - 3D shapes game from BBC KS2 Bitesize Maths

              - My students seemed to enjoy this game the most

Station 5

- Nets Challenge Game

     - As a group, pick a 3D Shape. Some examples might be:

          - Cube                  - Rectangular Prism

          - Pyramid              - Triangular Prisms

     - Assign measurements to each side length. 

        Draw the 3D shape below and label in all the appropriate 

        measurements.

     - On square dot paper, take turns drawing as many 

        different nets as possible.

     - Score two points for a net not already used yet. 

        Score one point for a net already used.

     - If someone draws a design that you do not think forms 

       the correct shape, you may challenge them. Check their 

       design by cutting it out and folding it. If it does not form 

       the shape, no points are scored. If it does form the shape,

       you miss your next turn.

     - Play ends when  no one can draw any more nets.

     - The winner is the person with the most points.

     * Game adapted from the Math Makes Sense Textbook Series.

Station 6

- Workbook Questions

     - Our school provides individual student workbooks from the Math

       Makes Sense series and this center/station allowed students to work

       through questions regarding nets & 3D shapes for practice

     - I could check these questions for understanding during Station 3 or

       at the end of class

_________________________________________________

     After Spring Break we will wrap up our discussion on nets and move onto measuring surface area and volume of 3D shapes. Do you have any online resources, activities, tips for this section?