Fagskole used to be post-secondary, non-tertiary education, i.e. it was not considered college or university. The people attending fagskole have technical education from secondary school (videregående). It is, with other words, some kind of specialization for electricians, mechanics etc.
Recently, they are considered tertiary, and will provide "studiepoeng", just as "høyskole" or "universitet".

Not sure how to best translate it..