A fair number of experiments on animals is done for educational purposes. For instance aspirant-surgeons practice on animals before they are allowed, or animals are dissected just to teach students what an animal looks like from the inside.
Fortunately there are people who are developing alternatives, in order to prevent unnecessary animal suffering. One of these is the Microsurgical Developments Foundation. They have developed a pvc model of a rat, which could be used to practice surgery.
Another rat model developed by them is an enlarged model of a rat, which could be used to teach people the anatomy of a rat. This is demonstrated in the video below.
Of course, there is no reason why such models should not be made for other animals, including humans. Or even individual organs.