Comment by qsort

This is an interesting approach (and also raises interesting questions concerning the relative power of languages, i.e. how adding various features relates to moving from binary logic -> regular languages -> ... -> turing complete, but I'm overthinking it...), but isn't it a tad too limiting? You at least need recursion to do anything that isn't completely trivial in Scheme, even for a CS 101 course. Wouldn't you outgrow them so quickly that you'd end up with "just Scheme, but more annoying" within a couple lessons?