I saw this when Dinah Zike presented at NSTA last year (Boston). I thought what a fabulous way to get more space out of your notebook pages! Not only can you present information on the flip up page but then students can write more information underneath. This method is featured in her notebooking book (http://www.dinah.org/).
I have been experimenting with glue verses tape. The first picture I taped the map down (taping edge to edge....if you use tape do not go past the edge or it no longer flips up as smoothly) the other two pictures I glued the top portion down (that is probably the best way to go. I was just experimenting with the tape).
Picture #1 - I downloaded a map of all the countries that use the metric system verse the standard system. Underneath students created a simple "cheat sheet" to help them remember that a millimeter is approximately the size of your pencil tip, centimeter as wide as your finger, etc.
Picture #2 - Students were compairing and contrasting rainforest plants and desert plants. Their written work is underneath the flaps.
Picture #3 - I wanted the students to really be able to tell me the difference between autotroph and heterotroph so I isolated those two words from the reading above it and had students create flaps that defined it underneath and then they had to draw a picture to help them remember.
My elementary students love the "flip flaps" (that is what they call them).