How to Make a 3D Pyramid With Cardboard
- 1). Measure and draw on a square on a piece of cardboard, 3 inches long on all four sides. Cut it out with a pair of scissors.
- 2). Measure and draw on another piece of cardboard a triangle 3 inches long on all three sides. Cut it out with a pair of scissors.
- 3). Trace the outline of the cut-out cardboard square in the center of a third piece of cardboard, using a pencil. Erase small segments of the pencil lines so the entire square outline consists of dotted lines.
- 4). Lay the cut-out cardboard triangle flat next to the dotted line square so the bottom edge is lined along one dotted line, and the point faces away from the square. Trace the outline of the cut-out triangle with a pencil. Repeat the process for the remaining three dotted lines. The result should look like a star with four points.
- 5). Create the unfolded pyramid by cutting out the star shape using scissors. Do not cut along any dotted lines. Turn the unfolded pyramid over so the dotted lines face down. Decorate the face-up side of the unfolded pyramid as you desire with colored markers or crayons.
- 6). Turn the unfolded pyramid back over so the dotted lines face up. Fold one triangle-shaped flap in toward the center square, along the dotted line. Open back up and repeat for the other three triangle-shaped flaps.
- 7). Fold all four triangle-shaped flaps in at the same time, until the four points meet in the center. Hold the top points together with your fingers. Tape each of the four corners together at the bottom using transparent tape.
- 8). Tape the top four tip points together at the top of the model pyramid. Repeat Step 3 through Step 8 to make additional pyramids. Make larger pyramids by increasing the length of the cardboard square and triangle. Ensure all sides of both shapes are the same length.
