It would be useful to know exactly what you propose to teach, and to what grade students. Your quote, to my Canadian eyes, implies grade 1 to grade 7?
For grades 1-3 I'd be tempted to use a simple all-in-one robot like the Parallax Scribbler 2 to teach flowchart based programming.
Using inexpensive arduino compatible boards for teaching simple introductory electronics, using a Pi to run the Arduino environment, has the advantage of limiting the potential damage to the cost of a replacement arduino clone.
Put one of the small prototyping / breadboard shields on top, and you are ready for simple circuits.
Personally, I would not risk frying a $35+ Model B, when I can risk a <$10 arduino clone
rsvbod wrote:Being in education you know that progression is important. My current school (I'm an international teacher) teaches scratch to year 7. So my thinking behind it is that they can grasp the basics with hands on electronics and become familiar with the programme.