As a former K-12 Technology Director who had to support the teachers of those type classes...

Check on the ACM curriculum recommendations. http://www.acm.org/education/curricula.html and http://acm.org/education/k12/k12final1022.pdf

Also the College Board. http://apcentral.collegeboard.com/apc/public/cours es/descriptions/index.html

Due to the fact that the College Board Computer Science AP test is given using Java, I highly recommend that in place of C/C++ as the language framework for teaching the concepts. Any language chauvinism aside, Java tends to be easier for beginners to grasp since it has far few "dark corners" to get into. Those dark corners are invaluable to programmers who need them, but for learning they tend to be counter productive. My son placed out of his first two programming courses due to AP, though that was a few years ago when the test was given in C++. Java is very much derived from C/C++ so you should have relatively little trouble adjusting yourself. You'll also find active online communities of other HS Computer Science teachers so you can find/share resources there, especially for things such as appropriate texts for the earlier courses (the AP courses should use the same texts as nearby colleges) and appropriate programming environments for whatever your computers are running.

Personally, I suggest that you start students in a simple web environment using a plain text editor, then once the programs become non-trivial, move into either Eclipse or Visual Studio, or at least get a good language aware programming editor. It will take about a week or two to get them used to the environment, but it pays off big time for debugging and general productivity.