I signed up to be a Let's Talk Science volunteer earlier this school year. I'm partnered up with St Mark Catholic High School where I went from grade seven to OAC (i.e. grade thirteen).
My main goal of joining this outreach program was to get students interested in computer science, so I put together a document that summarizes CS Unplugged activities, and suggests what kinds of classes could be connected to the concepts. So far, I haven't received any response from teachers at St Mark, but I think the recent Let's Talk Science newsletter was supposed to mention it. If that doesn't work, I may try contacting schools directly, because I think these activities would be very valuable for students taking computer (and other) classes.
The teacher I'm partnered with at St Mark (along with two other volunteers) teaches grade ten science, which covers topics in chemistry, biology, and physics. Because physics can be kind of dry, the teacher was hoping we could put on an activity to demonstrate concepts of velocity and acceleration. After searching around for ideas of hands-on activities, I found that they were too easy or short for a grade ten class. Instead, I decided to format the activity as a team competition that included questions from the text book and some of the more hands on activities. The result is the Physics Olympics. I'm hoping we will be able to perform this activity soon.
If you think you can use either of these documents, please feel free; just remember to credit me as the source.