My Career in computers started off by working to create Military Simulators in the mid 90s. At the time we were able to create fairly detailed simulations but it took hardware and computers that costs hundreds of thousands of dollars. That experience has stayed with me and I now believe that simulation is about to explode into the world of education.
There is a type of learning called experiential. This means you tend to retain more information when you can obtain it firsthand. This makes perfect sense to me. I can read about Niagara Falls in a book for example, but it is a much more rich experience to actually be there. The current state of the art in simulation can be found today not in the military but in video games.
For example, there is a new game called Space Engine. This is an amazing tool for learning about astronomy and the universe.
Here is a overview video by Anton Petrov that covers how mind blowing the simulator is.
The technology to do this is decreasing in price and increasing in power all the time. I think in the near future we will start seeing whole virtual worlds being created for the sole purpose to learn.