The Breton translation of The Hobbit makes an excellent reader for use with a suitable grammar and dictionary and with the Cornish edition beside you as a 'crib'. Go to Literature and click on An Hobys.
There is an Irish translation of The Hobbit as well. If your interests include Irish you may wish to compare the Cornish and Irish versions, because the translator in both cases was Nicholas Williams.
Here is a link for Breton correspondence courses: