I've not kept track of the latest rules/changes to ED visas, but I have a friend visiting in a month or so (coming in on a Tourist Visa) who'd like to be able to convert that into a 1 year Education Visa whilst he is here . . . can that be done without having to leave Thailand for any reason?

It is not possible to get a one year visa on any kind here in the country.

If a person was attending a university they might be able to do a change of visa status to a 90 day non immigrant visa entry at Bangkok immigration only and then after 60 days apply for a one year extension of stay.