The Oregon Trail is an educational game that tasks the player with completing an arduous wagon trek from Independence, Missouri to the Willamette Valley in Oregon. It was designed primarily to teach schoolchildren about the experiences of 19th century pioneers colonizing the west coast of the USA, but its engaging and challenging gameplay is head and shoulders above many games billed as "educational." It remains a shining example of how to effectively combine teaching and fun in games.
In The Oregon Trail, the player assumes the role of the head of a wagon party that has decided to attempt the difficult journey west in the hopes of starting a better life on some of the cheap and plentiful land in the newly minted state of Oregon. At the beginning of the game, the player chooses their character's name and profession as well as the names of the four party members. The profession one chooses effectively serves as the game's difficulty mechanic as these choices determine the player's starting cash, special ability, and score multiplier. For example, choosing the banker profession provides the player $1600 (the most starting cash) but provides no special ability or score multiplier while the carpenter, who starts the game with $800, is more likely to repair broken wagon parts, and receives a score multiplier of 2 (See the image for the complete list of professions).
The player must then carefully provision their wagon with food, clothing, hunting supplies and spare parts, as well as selecting a team of oxen to haul the load. The trick here is to not overload your wagons by weighing everything's necessity. Overloading the wagons will slow the rate at which your party travels forcing you to survive on the trail for a longer period.
Once on the trail, the player has to balance the morale and health of their family and beasts of burden against the need to travel quickly enough to reach Oregon before winter closes in, all while managing their dwindling supplies. This is done by selecting the pace at which the wagon party travels (Steady, Strenuous, or Grueling) as well as the size of the meals provided to the party (Filling, Meager, or Bare-Bones). There are few opportunities to re-stock equipment after setting off, barring a few Native American trading posts and some extortionate stores in forts and towns along the trail. The player can always supplement their food supply by playing a fun hunting minigame (providing they remembered to bring enough bullets).
As well as forts and trading posts, the trail is dotted with interesting landmarks and treacherous river crossings. When confronted with these crossings, the player must decide whether to caulk the wagons and float across, attempt to ford the river, or wait and pay the ferry to cross (each decision comes with it's own dangers and drawbacks). Along the way the player will be hit with (usually negative) random events, which can range from one of the wagon's wheels breaking, requiring a brief stop and a spare, to a member of your party being stricken with dysentery or cholera, usually leading to death not long after. Deaths in the party leave a tombstone by the side of the road which will appear as a landmark on following playthroughs, making repeat playings a grim reminder of those who have been lost on the trail (or a hilarious reminder of that clever epitaph you wrote).
If the player makes it to Oregon, they must either take the Barley tole road or raft down the Dalles. Choosing the Dalles makes the player complete a white water rafting mini-game to reach their final destination, where they are awarded a score and rank based on how many members of their party survived the trip, the speed of their journey, the provisions they had at the end, and the difficulty of their starting profession (see image for breakdown). This score is then placed on a scoreboard and given a ranking depending on where it falls in the top 10.