Stick bugs need to be kept in an enclosed habitat. A 10-gallon aquarium with a screen top makes a good home, as long as there's enough room for the insects to hang. Stick bugs molt their skins by hanging upside down with their heads pointing down. They eat leaves, but the specific type of leaf varies with the species. Many will eat oak, ivy or ficus leaves. Replace the leaves when they start to wilt. Extend the life of the leaves by cutting a hole in the lid of a small container, filling the container with water and poking the branch through the hole. Mist the tank with distilled water to raise the humidity and to provide water for the bugs to drink. They get their water by sipping drops that collect on the leaves. Lack of space and humidity leads to improper molts, which can be fatal.
Have students draw scientific illustrations of the stick insects and the food they eat. Stick insects go through incomplete metamorphosis, so the nymphs of most species look like miniature versions of their parents. Have the students draw pictures of the egg cases, nymphs and adult insects. Students can label each part of the insect, such as the head, legs, thorax and abdomen. Have them draw pictures of the leaves that the bugs eat.
Discuss how appearance and behavior of stick insects increases their chances of survival. They tend to stay very, very still. When they do move, they sway back and forth, mimicking the motion of a leaf or stick blown by the wind. They climb using the hooks on their feet. Have the students hold the insects carefully. Stick insects don't bite, but some of the thornier species can pinch with their legs. Avoid keeping the American walking stick, Anisomorpha bupestroides. PetPlace.com says this species can spray acid that can cause temporary blindness.
Stick insects have an ability that few other animals have. You can set up a breeding colony of stick bugs, even if you don't have any males. Some species of stick insects can reproduce using parthenogenesis. The female stick bug will lay eggs that hatch into exact clones. Have students offer hypotheses on how this happens and the advantages and disadvantages within this method of reproduction. Stick insects tend to lay a lot of eggs, so if you have a healthy colony going, students can take them home to keep as pets.