In a Worker Placement game, players have some number of tokens representing their workers. These can be assigned using a few different mechanics to sets of actions in the game. The actions, and when they can be performed, often dictate how players earn points or advanced towards possible victory conditions.
As one of the broadest mechanics it can often depend on what it is paired with that determines which soft skills can be fostered and/or how well it matches an educational setting.
In each game the Worker Placement mechanic helps foster a students critical thinking skills as they try to get better at playing the game, but each game is very different due to the varied mechanics used and how they are interrelated to develop the game's rules.