We had a sort of aprenticeship, but this was mainly for luvvies [warm props] when I was a wee baren in theatre - back when in the dark ages of a previous life.
But it sounds a great idea b6307.
However as far as techie aprentices go, they were tied to  a trade required in theatre.
Maybe it something worth exploring in ameatre, I instigated a 'Stage craft Guild' once upon time, with various levels of achievement. But like all good things, it eventualy was flushed down the dunny! Not from a lack of interest, but from theatre groups internal politics.
the levels were 'Hands' 'Crew' & articipher' on a performance basis & emperical skills. [for want of better titled designations]
It seems a great concept to build & retain membership though, looking forward to further posts from members here, as I feel it could be a brilliant system, my mob cpuld get in volved with.
It would be good to know if formal indentures are utalised. Or just any set of made up falsies will do?