On this page of our guide to Psychonauts 2 we've listed the Nuggets of Wisdom available in Compton's Cookoff.
There is only a single Nugget of Wisdom in this level.
Nugget of Wisdom 1
Location: Foul Line Overlook.
To get to this secret, you have to jump off the neon sign next to the building. Then climb to the top of the building using ladders.