What you need are examples of the same situation seen from two different perspectives, moving differently. So for example if you can find a video of a car race showing what it looks like from the drivers point of view, that is the car appears stationary and the track appears to be moving. Then show it from the perspective of someone on the ground, where the car appears to be moving and the track appears to be stationary. I think it is important to stress the word appears in this work to begin getting students to understand that all motion is relative, depending on the position and motion of the observer. You might also find images of persons on a roller coaster. I'm sure there are others, some one on a moving boat, as compared to being on the boat.