The Kahn Academy site has really focused our attention on creating multimedia tutorials for math and other subjects. Classroom teachers are engaging their students in the thinking and creation processing that takes place when designing and publishing screencasts as in the Mathtrain site.
One of our fifth grade teachers, Margi Weaver, recently taught her students a math lesson using the ScreenChomp app on the iPad. Take a look at the post on the iPad Pilot blog that describes the advantages to using this instructional technique.There are plenty of screencasting apps so do share which ones are working in your classrooms. I have to say that ScreenChomp should allow for uploading to their site while providing a unique URL for easy sharing. However, this was not the case for our students as they received error messages. Update: 24 hours later we were able to upload the screencasts. The students were given specific URLs to access to view their videos.