This must have varied significantly with geography. In Ontario, Canada,
where I grew up, Commodore was king, both at home and in schools. Most
schools' first computers were PETs, either alone or in clusters, followed
by C-64s. There were some Apples around, but they were much more expensive
(even to schools) than Commodores. Proof of this was the strength of the
Commodore (TPUG, Waterloo Basic) and Amiga communities in Ontario.