I think so; ideally you (the teacher) would know a fair number of languages well so that you could match one of those with the student(s) and goals.<p>CS: Scheme and SICP or a less intense book.<p>WWW: Javascript (well, after I brushed up).  mikeryan has the right idea here, and it probably would be a great match for a bunch of high school and even younger students.<p>Prior to Javascript and DHTML VB might have been a good choice for the same reason (I'm assuming the edit-compile-run cycle was fast).  VB prior to VB.NET wasn't <i>that</i> ugly.