Open the graphics creation program on your computer. A blank worksheet will automatically appear on the screen. With Windows, this free program is called "Paint" and with Mac OS X this software is called "Paintbrush," and you can download it for free from Apple.
Select the line tool from the Shapes group at the top of the page if you're using Paint and then click "Size" to choose a line thickness of your choice. Select the line tool from the task bar on the left side of the page if you are using Paintbrush. Click within the worksheet and hold the left mouse button. Drag the line to a location that is about two inches away. Let go of the mouse button. A line will appear on the screen.
Create two more lines that are the same size as the one you just created. As you're drawing the lines, attach them into a triangle.
Draw three more triangles that are the same size as the first you drew. As you're drawing them, place their bases together in the middle of the page so that a square is formed in the middle of the four shapes.
Click on the "File" menu in the program, select "Print" and print the sheet with the four triangle shapes.
Cut along the outside line of the shape made by the four triangles and one square. As you cut, ensure the point of contact between two triangles is intact; don't cut out the triangles.
Discard the paper that was around the large shape and place it face up on a flat surface.
Bring two of the points that are beside each other but not touching the square together above the square.
Place a small piece of clear tape along the side where the two pyramids are touching. Lightly press each triangle side into the tape.
Join the two other triangles together and tape their sides that are touching. Tape together the two remaining sides that are not yet joined. The structure of your pyramid is now formed.
Dab your glue stick all over the pyramid structure and then toss some sand over it. Continue gluing and applying sand until it looks like the pyramid or pyramids being studied.
Allow the glue to dry for at least 10 minutes before you move it.