Flight School xplane 12 disapeared

I teach flight to middle schoolers and we spent a great deal of money to get three good simulators. The kids were learning a great deal using the flight school. But when the system updated the flight school disapeared. We are unable to figure out how to get the flight school back.

I was told that we may need to purchase it as an upgrade, but are unable to find this info.

Any help is greatly appriacated,

DSteele