How fun. We explored those tunnels at length circa 1985, but eventually got caught (Officer McBee, I still fondly recall your anger) and put on a year's probation. Apparently we'd be straight-out expelled now.
We did fib to her about how we got done, pretending we'd found an open door. The truth probably would have guaranteed our getting expelled - someone had loosened an elevator control panel, which allowed us to open it and flip the key-switch that sent us down to the basement and the tunnels.
Pretty stupid, in retrospect.