where do we get a parking pass?

In the office or online you can get discounts in the office

There are kiosks around the park. When you purchase the parking pass it has you fill in your tag number. I didn't see an option for any discounts you may be eligible for so if you are wanting a discounted pass I would go to the park office.

Kiosk outside park office,if its annual pass you can get them at the park office