Playing Games and Learning on PLATO: 1960 to 2015 The History of Computing

PLATO (Programmed Logic for Automatic Teaching Operations) was an educational computer system that began at the University of Illinois Champaign Urbana in 1960 and ran into the 2010s in various flavors. 
Wait, that’s an oversimplification. PLATO seemed to develop on an island in the corn fields of Champaign Illinois, and sometimes precedes, sometimes symbolizes, and sometimes fast-follows what was happening in computing around the world in those decades.
To put this in perspective - PLATO began on ILLIAC in 1960 - a large classic vacuum tube mainframe. Short for the Illinois Automatic Computer, ILLIAC was built in 1952, around 7 years after ENIAC was first put into production. As with many early mainframe projects PLATO 1 began in response to a military need. We were looking for new ways to educate the masses of veterans using the GI Bill. We had to stretch the reach of college campuses beyond their existing infrastructures.
Computerized testing started with mechanical computing, got digitized with the introduction of Scantron by IBM in 1935, and a number of researchers were looking to improve the consistency of education and bring in new technology to help with quality teaching at scale. The post-World War II boom did this for industry as well. Problem is, following the launch of Sputnik by the USSR in 1957, many felt the US began lagging behind in education. So grant money to explore solutions flowed and CERL was able to capitalize on grants from the US Army, Navy, and Air Force. By 1959, physicists at Illinois began thinking of using that big ILLIAC machine they had access to. Daniel Alpert recruited Don Bitzer to run a project, after false starts with educators around the campus.
Bitzer shipped the first instance of PLATO 1 in 1960. They used a television to show images, stored images in Raytheon tubes, and a make-shift keyboard designed for PLATO so users could provide input in interactive menus and navigate. They experimented with slide projectors when they realized the tubes weren’t all that reliable and figured out how to do rudimentary time sharing, expanding to a second concurrent terminal with the release of PLATO II in 1961.
Bitzer was a classic Midwestern tinkerer. He solicited help from local clubs, faculty, high school students, and wherever he could cut a corner to build more cool stuff, he was happy to move money and resources to other important parts of the system. This was the age of hackers and they hacked away. He inspired but also allowed people to follow their own passions. Innovation must be decentralized to succeed.
They created an organization to support PLATO in 1966 - as part of the Graduate College. CERL stands for the Computer-Based Education Research Laboratory (CERL). Based on early successes, they got more and more funding at CERL. Now that we were beyond a 1:1 ratio of users to computers and officially into Time Sharing - it was time for Plato III.
There were a number of enhancements in PLATO III. For starters, the system was moved to a CDC 1604 that CEO of Control Data William Norris donated to the cause - and expanded to allow for 20 terminals. But it was complicated to create new content and the team realized that content would be what drove adoption. This was true with applications during the personal computer revolution and then apps in the era of the App Store as well. One of many lessons learned first on PLATO. 
Content was in the form of applications that they referred to as lessons. It was a teaching environment, after all. They emulated the ILLIAC for existing content but needed more. People were compiling applications in a complicated language. Professors had day jobs and needed a simpler way to build content. So Paul Tenczar on the team came up with a language specifically tailored to creating lessons. Similar in some ways to BASIC, it was called TUTOR. 
Tenczar released the manual for TUTOR in 1969 and with an easier way of getting content out, there was an expl