The Jupiter Ace was before my time, but I found the user manual to be a very well written Forth tutorial: https://archive.org/details/Jupiter_Ace_Users_Manual_1982_Ju...

Steve Vickers was my university lecturer circa 1995. His course was legendarily difficult, in contrast to his lucid tutorials in both the Jupiter Ace and ZX81 manuals! The list of his papers on Wikipedia should give you a flavour of what the course was about: https://en.wikipedia.org/wiki/Steve_Vickers_(computer_scient...