Screencast can help students because they can communicate with eachother about a project they might be working on by sharing their thoughts and giving feedback to one another. Jing could also be used by a teacher to help show students a step by step process of a certain activity or program on the computer that they might use and then they can see it on Screencast.
Skype can also be used in the classroom in many ways. Many classroom teachers use the notion of pen pals to help students improve their writing. Through Skype, students could actually have a video conference with their pen pal and see what they look like. Other possible ways to use Skype in the classroom is when learning content through themes. For example, if students are learning all about Califonia, the teacher could get in touch with another teacher in California and the students can interview the real people from California... or Australia or wherever else you might imagine. Mediums such as Skype can give students an authentic means of learning. In fact, I use Skype on a regular basis to talk to my friend that moved to Australia this past year. Without Skype, we probably would not have been able to keep in touch as much as we have done. I love Skype!