1. Start by finding the length of the toilet paper roll. Most toilet paper rolls are about 4", but you want your mirrors to be exactly as long as tube, so precise measurements matter!
2. Next, we need to find the exact width of each mylar sheet panel in order to make an equilateral trianglular prism that will fit inside of the tube snugly without getting squished. This means that we have to divide the circumference of the circle into three equal lengths, then measure the distance across the circle from one point to the next.
This calls for a protractor! Protractors are a measuring tool that allow us to measure how many degrees are in any angle. A circle has 360 degrees (˚), which we need to break up into 3 equal sections: 360˚ divided by 3 equal sections = 120˚ degrees per section.
Take a marker and mark a dot anywhere on the edge of the tube. Use the protractor to measure 120˚ from your dot and mark it on your tube.
Measure another 120˚ from your last dot and mark your new dot. Repeat one more time - and your last measurement should bring you right back at the beginning! If you find that your starting point and ending point don't line up, check your measurements again.
Alternative method: If you don't have access to a protractor, use a piece of string to measure the circumference of the tube. Then, use a ruler to divide up that circumference into 3 equal lengths. Mark those distances on the string, wrap the string back around the tube, and then mark the tube to correspond with the marks on the string.
3. Now that you've marked the three points where your triangular prism will touch inside your tube, use a ruler to measure the distance from one mark to the next across the opening of the tube. Aim to measure as precisely as possible.
Once you find the distance between two points, measure the distance between another set of two points. Did you get the same measurement? Repeat for the last pair of points. Is your distance the same between each set of points?
4. Now that you have the length and width needed for each mylar panel, use a marker to draw out your three identical rectangles needed on your mylar sheet. Marker lines can be easily wiped away, so if you make a mistake, it's easy to "erase" and try again.
5. Carefully cut along the lines you've drawn on the mylar sheet to create three identical rectangular panels.
6. Lay the three individual panels down on the table. Pick the better side of each panel - as you may have marked up or scratched one side while cutting - and face that side down. Carefully line up each panel next to each other such that their long sides are side by side. Take a piece of scotch tape and tape together two panels along their meeting edge. Take another piece of scotch tape and tape together the remaining two panels together along their long edge.
7. Flip your taped mylar panels over and fold up together the last two edges to form the triangular prism. Carefully pinch the edges together to hold the triangle in place while you tape them together.
8. Slide the triangular mylar prism inside the toilet paper tube. If the mylar sheets don't fit, you can pull out the prism, cut off the tape, and fine tune your cuts to adjust the panels. If the mylar sheets fit in loosely, simply add extra tape inside the tube to help hold the mylar sheets in place.
9. Create a "lens" for the kaleidoscope by cutting off the bottom of the 5oz paper cup, leaving a small lip. The cut-off bottom should fit perfectly over one end of the toilet paper tube. Use a hole punch to make a hole in the center of the paper cup cap. You can also use cardboard to create a perfectly-fit circle to cover one end of the tube. Tape the paper cup cap or cardboard circle to the tube's end.
10. Now it's time to create the decorative disk! Use a compass to measure a circle on the white poster board that has a 2" radius. If your student has never used a mathematical compass before, this is a great time to explore the tool and learn how it works!
11. Cut out the circle you drew in Step 10.
12. Decorate your circle with any kinds of gorgeous designs you wish!
13. Take a sharpened pencil and poke a hole in the very center of your disk. (You can also use the pencil included with your compass.) The hole should be about the same size as the width of the straw, but just a bit smaller. You should have a leftover pin-prick mark from your compass to help you find the center. If not, flip over your disk to the blank side and use your ruler to draw a horizontal diameter and vertical diameter through the circle. Where your lines meet is your middle!
14. Cut a piece of straw between 3"-5" and tape it onto your tube such that about 1" of straw is sticking out from the tube on the side opposite of your eye lens.
15. Slide your decorative disk onto the straw, poking the straw through the hole you poked out in Step 13. The disk should fit snugly onto the straw such that it doesn't fall off, but allows you to spin the disk.
16. Decorate your kaleidoscope! Use markers, crayons, glitter, construction paper, or even wrapping paper to decorate your tube! If you want to cover your tube in wrapping paper, just take off the straw, wrap your kaleidoscope in wrapping paper, then tape the straw back on.
17. Look through your kaleidoscope, spin your disk, and see what kind of beautiful patterns emerge! You can also always create new colorful disks with all kinds of different patterns, and simply replace the disks anytime you want for a new kaleidoscope experience!