Head down the path a bit and you'll see a broken log going into the water on your left, jump on that, but don't go in the water, go left down on the brim of the water and there is a Psi-Card there. Now head up the log on the other side of the water (not the side you came from) and back towards the little shack Cruller is out front of. Continue past the shack and there is a large rock platform you can get up on with a Psi-Card. Now you can jump back towards that shack and go in a hole in the roof. In here is a complete Psi-Challenge Marker. Jump on the table and exit via the roof hole.
Now go back up by the ledge we jumped here from, but don't get on it, just head left past it and you'll see various rock ledges, one that has a nice dancing Psi-Card on it. From there look down towards the fence and to the left you can see another Psi-Card, but beware that the bear is also down there. Follow the logs to the right of the bear and this card to find 2 more cards before coming to an area with 2 geysers, one which has something stuck in it, but we can't do anything about that quite yet.
Follow the logs further in the same direction to another card, from that card make a hard left around the tree and you'll see another card not far away. Continue straight ahead and you'll see an entrance that looks similar to the bear's cave we saw before, but it actually leads to the Boathouse and Lake, so enter on in through there to check out the area.