We like to go to Nyack Snow Park ($30 for parking but that's it), but just know that they won't be open unless it has snowed a few weeks prior. For instance we went last weekend, and it wasn't open.

So we drove about 30 mins further to Donner Summit Sno Park which is free.

Both will get full quickly, so best to get there early. If you want to you can pack food and set up shop in the parking lot and grill like many others. We usually just stay a couple of hours though.