At the ground control position learn to give perfect clearances and control traffic on the airport movement areas.
ATC scenarios are individually programmed to give students the best opportunities to learn phraseology, situational awareness, and procedures.
On the local controller position safely take off and land aircraft in your airspace, coordinate with other cab positions, and operate real world equipment.
To be a great controller, students need to know what it's like on the other end of the mic. Students act like pilots controlling aircraft and giving radio calls.