What screencasting tools can be used for online teaching
Fingers crossed that this one doesn't get closed. I've tried to do something similar, but it hasn't come out well. Hoping that some others have suggestions.

It looks like they're using some sort of overlay or whiteboarding software, and I assume a tablet or stylus. I can see a cursor where their pen is drawing. 

I've tried this, and it didn't go well. But, I think that's more a factor of my handwriting than of the idea. Enough years of typing being my main method of written communication has made my handwriting terrible. And it's even worse on a Wacom tablet. Same thing with some student created videos. They're just hard to read.

I'd like to find whiteboard software that also allows typing. Haven't found one yet, although I haven't looked all that much either.

A couple things that have worked...

If I'm in a hurry, Powerpoint has enough animations built in that it's possible to do a fairly decent job. And, they can be exported to videos if you want to upload to YouTube.

When I've had more time I've used Flash. It's deprecated now, but I still have an old copy on my computer. Takes longer, but gives me a little more freedom in what I build. Also can be exported to a video, which is especially important since browsers are starting to frown on Flash. 

Edit:

Just played around with the pro version of Acrobat and it looks like it has a pen and text tool that might work for what I'm trying to do. Most of the time I'm just trying to annotate what's already typed out.

Edit 2 - After "screen casting" was added

This year I started capturing my screen as we work through problems and then uploading to YouTube for kids that missed the day or just want to go back for a refresher. I'm using a program called OBS. Works really well. A little Googling brought me to a Windows program called ZoomIt that will let me write and type over the screen as I'm demoing. Think I might bring my Wacom tablet to class tomorrow and give it a try.