You can learn Cornish by distance learning, and following a couple of links I found myself at Kernewek Dre Lyther.
They have a comprehensive list of materials, and you pay for a first level course, which includes an audio cassette and a tutor to mark your written work. I haven't yet taken this step, I downloaded the materials included some MP3 files so I can play them when it is a quiet moment and study at my own pace without feeling like I am falling behind a schedule.
So far I am still on dsykans onan or lesson 1, the similarities between Cornish and Welsh (Cornish is one of the family of Celtic languages, closely related to Welsh and Breton and slightly more distantly to Irish, Scots Gaelic and Manx so work that one out if you can) are there but there are differences generally in the mutations of the word.
According to records by the nineteenth century, Cornish had died as a spoken community language, although there are records of the language being spoken particularly at sea by Newlyn fishermen. During this century there was a resurgence of interest in celtic culture which meant that Cornish attracted some academic attention. The plays of the middle Cornish period were re-visited, and academics such as Edwin Norris and Whitley Stokes published them with commentaries and translations. It was not until early in the twentieth century, however, that an attempt was made to revive the language.
In 1904 Henry Jenner published his Handbook of the Cornish language, based on the texts available to him at the British Museum. This kick started the revival of Cornish as a living, spoken language, and Jenner's work was picked up and continued by Robert Morton Nance, who researched and gathered together more fragments of the language, finally developing a regularised spelling system based on the medieval texts, known as Unified Cornish. The revival continued to grow throughout the early twentieth century, with evening classes, events and examinations being established as well as some teaching in schools outside the formal curriculum. Books and magazines were published for users of the language. The 1980s and early 1990s saw a time of review and reconsideration about the theory of reviving a language, plus additional research on the texts. This resulted in the proposal of different approaches which moved the language on from the initial research that Jenner and Morton Nance had carried out in the early twentieth century. In the early 1980s Richard Gendall began exploring the Cornish of the Late period. He worked from the premise that a language revival should be based upon the last available evidence from when the language was last spoken, and the form of Cornish now known as Modern Cornish grew out of this work. In the late 1980s, Dr Ken George carried out a great deal of research into the phonology of the language, including how this could be better linked to the orthography by a rationalised spelling system, and the result of this was the beginning of Common Cornish. Finally, in 1995 celtic scholar Professor Nicholas Williams proposed an amended version of Unified Cornish, called Unified Cornish Revised, which takes the texts of the sixteenth century as its main source.Despite what people (emmets) say, tiddy oggy isn't actually cornish in the current sense but a local term for a pasty...
So is Cornish, Cornish? There are those who would say that if a language is not spoken by anyone, then it cannot be resurrected successfully, but it seems to me that the basis for the language has been given its roots and that what we have is as close to the original as may be.