Teaching about sorting algorithms can be rather dry and dusty. For this reason I created Sorting for Teachers many years ago as a DOS program. As I remember, I had seen something similar that ran on the old BBC micros. The software was later updated to run on current versions of Windows. It shows an algorithm, along with a set of numbers to be sorted and a display showing the values of the variables.
I intend doing some more work on the program before releasing it again, but in the mean time I have used it to create some videos that could be used in the classroom. One shows the program in action, using the selection sort to arrange a set of 8 numbers in ascending order. The algorithm is highlighted line by line as it executes. The variables are updated in parallel and the set of numbers is highlighted and animated to show which ones are being compared and which are being swapped.
By using the play/pause button of video playing software, teachers can step through the algorithm at their own pace, explaining what is happening or getting students to say what will happen next, etc.
The second video just shows what happens to the set of eight numbers and is designed to introduce how the algorithm works, before looking at the code. Finally there is a third video that demonstrates the software and its features. However this may also be useful for teaching purposes, as it models one way of discussing how the algorithm works.
To view these videos, go to the Education Vision Consultancy books page and follow the YouTube video channel link.