If you are demonstrating to students with your mac you might be wiggling around your tiny mouse cursor in hopes that the students can see what you are pointing at. One of the features of the Mac allows you to make your cursor really BIG. Students will be able to easily see what you are clicking on.
Note that when you do a screen recording or a screenshot, the cursor appears small so this will not enhance your screencasts. I use mouselight, available in the Mac app store, to shine a spotlight on where my mouse is for screencasts.