National Geographic packs its site full of videos, web cams and photos. Take a close look at the animals at the Philadelphia Zoo. One thing that makes many primates different from human beings is their hands.
Some primates have no thumbs.
Others have thumbs that are placed differently from ours. Try doing some ordinary tasks without a thumb. Just cut the thumbs off a pair of old gloves and sew the thumb holes shut. Now that you've tried observing one human being and one animal, you can try observing humans in groups. During recess or lunch, spend some time observing your classmates.