Teacher: Mrs. Coenen
Date: March 25, 200x
- toilet paper rolls
- cardboard rectangles
- sticky mirror covering
Tell the class that our final project is going to be making kaleidoscopes, and that we will not have a final test on paper, but this project is going to use all the knowledge that we are learned so far in geometry.
- TLW be able to calculate the diameter of a circle (toilet paper roll).
- TLW be able to construct a circle using a compass and knowing the diameter, radius, or circumference.
- TLW be able to construct three identical rectangles that have the dimensions of the diameter of the toilet paper roll.
To make a kaleidoscope, the students will have to follow these steps:
- Find a toilet paper roll (empty), and have the students figure out a way to find it’s diameter, radius, and circumference.
- They may use yarn to wrap around the roll, but then when measuring the yarn onto a ruler, they will find a different measurement. This will not work, but will be a good discovery learning experiment.
- They may use rulers and try holding them up against the roll, but again, this will not be precise enough.
- They will need to use string that does not stretch.
- Once they know the diameter, they will use this measurement to create three identical rectangles. They will also need to know the length of the roll for the other side dimension. However, the length of the longer side of the rectangle must be about an inch smaller than the roll, so there is room to put the beads.
- Once the rectangles are made (out of cardboard), they need to put a sticky mirror covering onto the rectangles to create mirrors.
- Then with the three rectangles, they need to place these into the roll as a triangle. The fit should be snug. The mirror part needs to be facing towards the middle so that you can see it.
- Once this step is done, they are ready to create the circle that will cover exactly over the paper roll. This is very important that it fits exactly over the top, not too big, not too small. It may take them a lot of practice drawing circles and cutting them out to figure out the perfect one.
- After they have it cut out and see that it will work, they need to put a whole punch directly in the center of the circle as they eye hole. Then they need to glue this circle onto the top of their kaleidoscope.
- Now this step is tricky. Students need to make another circle, the size of the diameter, but now it must be a hair thinner than the actual diameter. It needs to fit into the roll very snug. Student will need to tell you the exact measurement to use, and the teacher will then create the circle on the shrinki-dink using the campus, but then cut it out as a square, so the student can make the actual circle cut out.
- Once done, place this into the roll and on top of the three rectangles.
- Put beads, or whatever transparent colorful objects they have, and put those on top of the shrinki-dink. They can not fill the entire space because there needs to be room for movement.
- Then to end, cap off the beads with Saran wrap and put a rubber band around it to keep it sealed.
Have students experiment with different objects to see the difference. Let them enjoy!
- Was TL able to calculate the diameter of a circle (toilet paper roll)? (written work)
- Was TL able to construct a circle using a compass and knowing the diameter, radius, or circumference? (written work)
- Was TL able to construct three identical rectangles that have the dimensions of the diameter of the toilet paper roll? (written work)