How I Use It
Code.org is a great resource for introduction and extension of learning coding in the classroom. If you help students create a profile, the program can be used for just a few minutes at a time without losing progress. There were some glitches during the hour of code week in 2014-15 due to overload of the system, but as the week went on, it performed much better.
This website is a wonderful resource (including links to other sites) when teaching coding. You can use it for all grade levels as there are courses for non readers up through those that have done this for years (much more challenging). The site had some problems during hour of code last year because the traffic was much higher than anticipated, but they were extremely responsive quickly at fixing the problems by adding servers. The resources that are available (posters, unplugged activities, etc) are top notch.