Your school experience sounds a lot like mine ~5 years ago. We also swapped the order at start of the first practice race, but only for the top half of the field. Since I was Joe slightly above Average in qualifying, I wound up on the Pole! #2 on the outside jumped me at the start.

For the second practice race, they were going to do something else, but the stewards thought I did such a great job pacing the field that I had pole again. This time I got a great start and held the lead for one lap. One faster guy passed me, but I was close on his tail. We headed into turn 2 in the drizzle, and he spun. I probably could have made it by, and easily "won" the race as the yellow behind me slowed everybody else. But he was a good buddy, and I knew that we both had to drive our cars home (that is, no trailers, these were streetable Spec Miatas). So to make absolutely sure there was no contact I went off on the inside.

Only time I ever lead a race... :-(