File Cabinet - Act 1
April 24, 2012
How many Post-It notes will it take to cover the file cabinet?
- Teacher noteBefore giving students the actual dimensions, have them make estimates. Use Mr. Stadel's height as a comparison. Use the link to Estimation180.com to find out Mr. Stadel's height.
I've included enough pictures to unveil the dimensions separately or all at the same time (the "depth" pic has all three).
Students might ask if Mr. Stadel will cover all six sides (faces) of the cabinet. This is an important question to address. Ask students what makes the most sense: all six sides, or just the five visible sides? Maybe have students come up with two answers.
When students are solving, encourage multiple representations in Act 2. Refrain from giving students any formula for the surface area of a [rectangular] prism. Instead, encourage students to come up with the most efficient way to calculate the number of stickies.
Upon completing Act 2 (early finishers) challenge students to:
*Derive a formula (process) for the surface area of a rectangular prism.
**Derive a formula (process) for the surface area of any prism.
***Address one of the sequel tasks.
- ImageFC-Act2-1 [ESTIMATE cabinet]
- ImageFC-Act2-2 [height]
- ImageFC-Act2-3 [width]
- ImageFC-Act2-4 [depth]
- ImageFC-Act2-5 [ESTIMATE sticky]
- ImageFC-Act2-6 [sticky]
- LinkMr. Stadel's height [Estimation 180]
If you had 1,000,000 stickies, what kind of file cabinet could they cover?
If the WIDTH of the cabinet was doubled, how many more post-its would be needed?
If the HEIGHT of the cabinet was doubled, how many more post-its would be needed?
If the DEPTH of the cabinet was doubled, how many more post-its would be needed?
How long would it take to cover if it took 40 seconds for every 5 stickies?
Would it be faster to write the numbers & stick? OR stick & then write the numbers?
What formula (process) could you come up with to calculate the surface area of a [rectangular] prism?