I added tree frogs to my special education classroom menagerie simply because I couldn't resist them in the pet store.  They fit in our palms, required little maintenance, and occasionally emitted a wonderful, deep-throated croak.  Later, we added a baby chameleon, although we were told that when the chameleon grew larger we would have to separate the animals because he most likely would try to swallow the frogs whole.
Anyone wishing to try tree frogs as a pet will need a medium-sized terrarium, a regulated heater in winter months, and lots of places for the frogs to hop and hide.  We used artificial branches and plants purchased in the pet store, but I have heard of people putting live plants and branches broken from trees in as well.  The frogs and chameleons both eat crickets, so that was handy, and must be kept moist at all times since they originated in a tropical environment.  The children loved taking turns spraying water from a spray bottle.  Both species are slow-moving and like to stay camouflaged, but they gave my students an enormous amount of pleasure, and even the children who had difficulty focusing on their school work would sit patiently watching and waiting.  Learning about the animals and their habitat became a joy rather than a chore, and example of hands-on learning at its best, I think.
Next time:  How a couple of birds became a passion that has filled rooms!