Does ipad air 2 have the same price at different Apple Stores in California?

At different Apple store, yes. Some other retailers may offer a small discount (Costco is about $20 cheaper, for example). but for the most part, it will be the same price regardless of where you buy it.

The Apple Stores will have the same price stated on the US website however like Kilgore-Trout said others may discount somewhat. Best Buy is also known to provide a discount, on Macs as much as $150.

Another source for comparison if you happen to be a fan of online commerce

http://prices.appleinsider.com/#ipad

Only time I've seen Apple outlets reduce the official cost of products is when new models come out and a mad "empty the warehouse" dash ensues. Apple powers-that-be really hate that and do all they can to avoid it, but it has happened.