Lesson Plan Title : Drawing Nets of 3 Dimensional Objects
Grade 9 through Grade 12 (High School)
Overview and Purpose:
Students will be able to use concrete materials to help them understand the concept of nets. Being able to take an object and spread it out flat is much easier to see in concrete terms rather than in the abstract.
The student will be able to draw a net of three different objects. Two of those objects will be able to be laid flat and one will not.
One cereal box for each pair of students (cut off the six overlapping tabs, three on each end)
One ice cream cone wrapper (with the lid taped onto part of it) for each pair of students
One short round candle for each pair of students
Discuss that a net is a 2 dimensional representation of a 3 dimensional object. Give each pair of students a cereal box, ice cream cone wrapper, and a candle. Have them unroll the ice cream wrapper so that it lays flat. Explain that this is a net. If they close the wrapper back up it makes a cone. Have them sketch the net in their math journals.
Have the students work with their partner to turn the cereal box into a net and sketch it in their math journals. Point out that six of the extra flaps are missing since they overlap on the ends.
Explain that often you have to visualize what the net will look like since things cannot be laid flat. Have them try to do this by sketching the net of the candle in their math journals. Come back together and have some students show their drawings. Make sure they included the ends of the candle in their nets.
Nets can be a very difficult thing for students to visualize. Giving them concrete examples that they can manipulate will help them understand the concept. If more practice is needed, students could create their own nets and 3-D objects out of paper and tape.