Using the chatbox feature (which almost all video call programs like Skype incorporate into their interface) to illustrate spelling and other language phenomena is also limited. In my field, English language teaching, I do a lot of pronunciation work, and I often use the symbols of the International Phonetic Alphabet to do this. There is no trouble-free way to type these symbols easily into a chatbox.
Most language teachers use timelines and stick figures to illustrate their teaching, and diagrams and quick illustrations are an essential part of how they do things. Especially if they've been trained as a classroom language teacher and have years in service in the classroom, language teachers feel crippled if asked to teach practically any language phenomenon without a board.
And so, they need a way to display these things to students.
Enter the online virtual whiteboard. There are a number of services, some free, some not, which present you with a browser window that has a blank area in it that you can write on using virtual drawing tools. In addition, these programs include a link which a student can use to view the window the teacher is working on. The student's view is updated in real time or after a short delay.
If you've used screen-sharing technology and are wondering why a virtual whiteboard would be better than using a drawing program installed on your computer and screen sharing to allow your student to view what you're doing in that program -- virtual whiteboards came into existence well before screen-sharing technology took off. Screen-sharing also uses up a great deal of both your and your student's transmission and reception capabilities to function properly -- it's generally like running a second webcam. A virtual whiteboard works more smoothly, provides a clearer picture, and doesn't cut as much into your transmission speeds.
You can draw on a virtual whiteboard with your mouse, but really, a mouse does not provide enough control to make accurate shapes and letters. Enter another tool called a graphics tablet. A graphics tablet is not the same thing as a tablet computer (which are all the rage nowadays). This is what a graphics tablet looks like:
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This is what a tablet computer looks like:
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People confuse them easily.
Graphics tablets take a day or two of practice to master writing on. They were really designed for graphics artists, and not as something to actually write on, so it makes sense that adapting them to virtual whiteboards can be difficult. But once you have it down, you can watch the screen and write on the pad and the cursor will move in the way you want it to. Graphics tablets come in all sizes for all budgets, but the best brand, the one professional graphics artists use, is Wacom.
One final note: many virtual whiteboard programs use a simplified graphics design drawing interface, and if you're not familiar with Adobe programs like Flash, Photoshop, Illustrator, and Fireworks, using the tools available may take a while to get used to. Add to that the complexity and unfamiliarity of a graphics tablet, and you might find yourself looking for ways not to use your whiteboard. This can be a trap that leads you down the road to developing a less-engaging teaching style than you might otherwise use. Few things add as much interest to online lessons as easily as well-managed, multicolored whiteboard work.