But (in reference to the parent topic of learning libraries vs. learning language primitives) shouldn't freshman CS students be mostly NOT using library functions? For example the classic exercises in sorting, learning various sorting algorithms, or manipulation of tree structures, matrices, etc. if you're just using library functions you aren't really learning what's going on.
Not really commenting on spaced repetition here, that should be helpful in either case.
At my university the freshman course was, for two years, taught in Haskell. To my eternal shame I managed to dodge most of the first year with a fistful of RPLs, so I never got to sample it.
The result was that lots of students dropped out of computer science and went elsewhere. More than had when being taught something else.
So they switched back to a intro course based on Java (which is their main teaching language for the first two years, C is the second language which is picked up in the 2nd half of the first year). Then you go on to bog-standard Data Structures & Algos / Computational Structures courses, Algo course etc etc which is where you learn the ins and outs of sorting, trees and so forth. Or, in my case, you barely do so because you are a lazy student who didn't do his homework.
The upshot is that you wind up spending most of the intro course teaching the mechanics of Java and motivating students with "interesting" examples. Various graphical geegaws, basically. In such cases students usually aren't using the standard lib, they're using a provided library.
Not really commenting on spaced repetition here, that should be helpful in either case.