Chapter+5+Project

__**Chapter 5 Project: Moving Entertainment**__

Beginning the Chapter Project

Pop-up cards and books, in which a flat piece of paper transforms into a three-dimensional

creation, enchant children and adults alike. Other books and cards with movable parts off er

things to spin or pull, or make a movement in some way. Surprisingly, “movable books”

date back to the thirteenth century; however, pop-ups or movable parts were not used in

children’s books until late in the eighteenth century.

In this project you will explore the geometry of triangles by using pop-ups. You will make

pop-up cards and then use the language of geometry to tell others how to make them.

Activities

__Activity 1: Building__

Follow the directions to make a triangle pop-up card. • Fold two pieces of paper in half. Set one aside.

• Hold one paper with the fold on the left, and fold down the upper left corner, forming a

triangle. Open up the paper to the inside, and label ABC and altitude BD.

• What kind of triangle is ABC?

• In addition to being an altitude, what other word could describe BD?

• Pull D toward you, and close the card so that ABC folds inside the card

like the fi gure at the right. Th e folds along AB and BD must be reversed.

When you open the card, ABC will pop up.

• Glue the other paper you folded in the fi rst step to the outside of your card.

Do not put glue on the pop-up triangle area.

• Decorate the card and pop-up. You can cut out a figure or an object,

fold it vertically, and glue it along BD, and it will pop up.

__Activity 2: Experimenting__

Follow the directions to make a “talking mouth” pop-up card.

• Fold two pieces of paper in half. Set one aside.

• Find the midpoint A of the folded side.

• Draw AB perpendicular to the fold.

• Draw isosceles CBD, which has base CD on the fold and altitude AB.

• Cut along AB; fold on BC and BD.

• Open the card, and pull each of the triangles to the inside of the card, as you did in the

previous activity. When your card is closed, it should look like the figure at the right.

• When you open the card, the mouth should pop open.

• Experiment with a non-isosceles triangle CBD.

• Finish your “talking mouth” card by gluing paper on the outside and decorating the card.

Draw an animal around the talking mouth pop-up.