When I started teaching, it was standard practice to use tracing paper to teach rotations. I never loved it, because it involved having to keep track of tiny pieces of paper, and find them year on year. One year I lost them when it was time to teach, so I had to come up with a different method on the fly. I’ve also seen rotations taught as a set of rules to memorize, depending on what rotation was being asked for. That is fine, too, but it doesn’t work when the center of rotation is not the origin (0,0). IGCSE often uses a centre of rotation that is not the origin, so I needed something that would work in every case.
Here’s my explanation. If there’s a way I could explain it more succinctly, please help me out with that. I tend to be wordy.
I used both vector format and letter coding, because when you introduce it, you want to show direction. When you introduce vector format, you have them start writing in that format. Honestly, it’s ok to only use vector, as long as student understand the x is on top and the y is on bottom.
I have seen that other teachers have done similar methods, but this is something I came up with on my own as I was trying to get students to picture the rotated image. Turning the paper helps a student to see what the image will look like, and it’s an easy check to see if the rotated image is turned correctly.
Do you have a different way to teach rotations? If so, please tell me in the comments.
Source: Image in video is from the Fall 2012 Paper 4 of the IGCSE 0607 Extended Mathematics exam.