Geometry Origami - Penguin What shape do we begin with?

Geometry Origami - Penguin Fold along the diagonal so that the white side is showing. What shape do we have now?

Geometry Origami - Penguin Rotate the triangle so that the right angle is on the bottom left.

Geometry Origami - Penguin Put a dot on the bottom edge, about 1 cm to the right of the right angle.

Geometry Origami - Penguin Fold the 45° angle which is to the right of this dot over so that it meets the dot.

Geometry Origami - Penguin What shapes do you see?

Geometry Origami - Penguin Unfold. Look closely at your fold lines. Do you see 2 squares with a diagonal going through both of them?

Geometry Origami - Penguin Look at the diagonal in the small square. Right now, this fold line is a “mountain”, because it sticks up toward you. Fold just this part of the diagonal in the opposite direction. It will become a “valley” because it will be folded down, away from you.

Geometry Origami - Penguin Now that our mountain has become a valley, we’re going to fold back into our trapezoid shape. Fold the small valley and tuck the small square inside the original trapezoid shape. Pinch the valley together.

Geometry Origami - Penguin Tuck the small square inside the trapezoid.

Geometry Origami - Penguin Now we’re back to our trapezoid. This time, the triangle is on the inside, not the outside. BeforeAfter

Geometry Origami - Penguin At the right angle, pick up 1 layer and fold it over to the short side so that it makes a triangle. Your triangle should reach almost to the end of the long side of the trapezoid, but not all the way. What kind of triangle do you have? How do you know?

Geometry Origami - Penguin Flip the paper over and repeat.

Geometry Origami - Penguin Fold the top over to the right to form the penguin’s head.

Geometry Origami - Penguin Gently unfold your paper until you get to this shape.

Geometry Origami - Penguin Look at the red line. Right now, this is a mountain fold. Fold in the opposite direction and turn just this part into a valley fold.

Geometry Origami - Penguin Gently fold back together. Your new valley fold should allow the penguin’s beak to turn inside out, so that it is all black.

Geometry Origami - Penguin Congratulations! You did it!