Skool Daze was created by David Reidy for the Zx Spectrum and Commodore 64 and released by Microsphere in 1985. It is one of the Spectrum's best-loved games.
While the constaints of the hardware at the time limited the size of the game world severely, the structure of the game was essentially that of the modern Open World concept that we know and love today.
The overall purpose of the game saw you attempting to obtain your report card out of secure storage on the school site before term ended and you failed the year. The card is being held in a safe and each of the teachers in the school knows one letter of a code, which you must obtain from them in order to open the safe.
To be able to retreive these codes however, you needed to (don't ask why) hit each of the trophy plaques which were dotted around the walls of the school, making them flash. Having obtained and amended you report card you then needed to return it to the safe, and de-activate the trophies 'so there was no suspicion' in order to pass the year. Clear? No? Good.
This is where the open world elements come in. You have an inital task of 'activating' all of the plaques in the school, and can go anywhere you like to achieve this. At the same time however you are supposed to be attending lessons with all the other children in the school.
The games life system revolved around being set lines by the teachers for bad behavior. Hit 10,000 lines and it's game over. So do you go to class, and attempt to keep your head down, or do you wander the halls and attempt to activate the trophies? Getting caught in the halls when you should be in a lesson catches you lines untill you get out of site of the teacher who spots you. But then, in some classes there are more students than seats and kids are constantly fighting for one. Getting knocked on the floor and being spotted by the teacher catches you lines.
The trick of the game was that for the majority of the plaques you needed to hit you had to punch / catapult a fellow student to the floor and jump on to him in order to reach the trophy. Getting spotted doining this means more lines.
Again, furthering the open world theme on this game is the fact that the school is populated bt a raft of other children who go about their daily businiess through the game - attending lessons, answering questuions from the teachers, wandering the halls and fighting at break times, writing cheeky messages on the blackboards.
Like all games of the era, it was basic fun, and it was basically hugely unfair but the open world spark is definitely what gives me the fond memories of it, that and the fact that I never played Elite.