Big Bear or Gorman... I grew up in Southern California and that s where my parents always took us for the snow. If you want to stay for a night and not just go for the day, I d head to Big Bear.
Since your Kids where under 21, your best bet is to contact condo / cabin owners directly to see if they will rent to you. Very few hotels or motels will accept under 21 visitors.Rather than give you a specific property name and location, I would suggest that you do some research on the available houses/condos, the prices and the locations. I have used justvr.com in the past and it was quite helpful for narrowing down my choices and booking a few nights stay.
Either Big Bear or Frazier park ( north of Gorman on I-5) but keep in mind if its raining here its snowing up there,, and The CHP usually closes the highway .
Another vote for Big Bear... they have a lot more hotel choices, as well as a snow hill with a rope tow (Magic Mountain).
big bear