Subjects like science and mathematics tend to use odd notations and diagrams a lot. One way of teaching or learning these subjects remotely is via a Skype session where each participant can view what the other is writing or sketching. The idea is to position a webcam over your writing pad, and one way of doing this is with a simple stand made from a wire coat hanger.
Many thanks to Peter Lees for this idea - I just took some photos and wrote it up.
Step 1: Prepare the Coat Hanger
Take a specimen of the common domestic wire coat hanger (Regalia Suspensis, subspecies Tin), pull it into a square/diamond shape, then 'fold' the diamond in half as per the images.
Step 2: Anchor the Stand and Position the Webcam
It's best to anchor the webcam stand to stop it moving around during the tutorial, e.g. by placing the flat section under your laptop or under a few heavy books.
Different webcams have different mountings, but the general idea to is to position the webcam on the hook of the coat hanger stand and hold it there firmly with, e.g., tape.
Step 3: Position Your Writing Pad and Adjust the Webcam's Position
Depending on the capabilities of your webcam, you may be able to adjust focus using software (e.g. Logitech C525) or by fiddling with a ring around the webcam lens. You may be able to adjust lighting through your webcam's software, or by placing a desk lamp nearby.
It's a good idea to check using your videophone software (e.g. Skype) that your writing pad is in focus and the writing is legible. If you choose to zoom in to a small area of the writing pad, you should keep in mind that the person you're calling can't see all of your pad.