Getting ready for Christmas decorating can easily be a lesson in geometry for anyone who is feeling creative. Tree ornaments, from photo frames to paper chains, start out as common geometric shapes and are transformed by holiday magic--and a little glue. You can talk about all the shapes you are making, if the artists aren't too excited to pay attention. Or let the lesson quietly sink in through the experience and just enjoy the fun.

Origami Paper Chains
Those beautiful packs of square origami paper with elaborate Asian designs make fabulous paper chains to hang on the tree. Even the smallest helper-elf can participate and the results will look terrific. A grown-up or an older sibling cuts the paper squares into even strips. These can be 1 to 2 inches wide---measure the paper so you can evenly divide it into strips. The colored strips of paper are mixed up and the first circle of the chain is made by simply swiping a glue stick over one end and tacking the ends together. Poke the next strip of paper through the loop, glue the ends into another loop and continue until the chain is finished. Be sure the patterned side of the paper forms the exterior of each loop.

Glittery Triangle Trees
Green construction paper, glitter, old Christmas wrapping paper, string, popsicle sticks, and some glue make versatile tree decorations. Cut a triangle 6 inches high from the green paper and glue on "ornaments" that are small circles of bright wrapping paper, made with a hole punch. A zig-zag glue swipe down the paper tree will look like a garland when it is sprinkled with glitter. The popsicle stick gets glued to the back of the tree with about an inch extending down for the trunk. Color this brown with paint or a marker. String that is glued to the popsicle stick allows the tree ornament to hang on the Christmas tree as a bauble. The string can also fasten the tree to a vase or tall votive candle to decorate a side table or mantel.

Paper Photo-Frame Ornaments
A school photo or wallet-size photo of a child makes a perfect ornament for the family's or grandma's tree, so make several to share. Cut red, gold and green heavy stock or construction paper into squares, rectangles, circles and triangles. Each piece should be larger than the photograph but the sizes of the shapes should vary. The subject of the photograph makes a frame by gluing two or three different shapes on top of each other so that the lower shape is a border for the one on top. Finally, the photo is glued in the center of the glued-together stacked shapes. A hole punched in the top of the ornament gets colored string or a wire ornament hanger through it and the geometric frame is ready to hang.