Later, a FCC license exam preparation course was added and, in time, courses were added for students aspiring to become tradesmen in the broader field of electronic equipment servicing, including: TV & VCR repair (NRI registered the term "teletrician" with the U. S. patent office in 1938), basic electronics, automation & control systems, avionic & marine communication systems, and even a very early computer technology (logic and programming) correspondence course in 1971. Eventually, NRI further expanded to include courses in electric appliance repair, automotive mechanics, small engine repair, building construction, home inspection, air conditioning, refrigeration, heating, & solar technology, computer repair, locksmithing, as well as bookkeeping and accounting. Nevertheless, radio-television-electronics remained its largest division. NRI was America's oldest and largest home-study radio-television-electronics school, a claim they frequently advertised. The school was an accredited member of the Distance Education and Training Council, formally known as the Home Study Council and now known as the Distance Education Accrediting Commission.