The ikastolas are schools which provide education entirely in Euskara. What does “bertsolari” mean?
It is the name in Euskara for an improvising poet who sings in public. The discipline is called bertsolarismo. From the website of the Basque Government you can access a text as an introduction to bertsolarismo, which covers from basic definitions about bertsolarismo and bertso (the poems) to schools where it can be learnt. At www.bertsozale.com you can also find detailed information on this subject.