You guys may already know this, but I didn't. As I searched for auto insurance quotes, a question that popped up was whether I had completed a Senior Driver Program. I had no clue, so an agent filled me in. If you are 55 or older, you can complete a CA approved Mature Driver class, and get a significant discount on your auto insurance.
You can find the programs offered by various parks, cities, senior centers, etc. You can also take the course online, which is what I am doing. I'm using this program, but it looks like there are many of them out there: California Mature Driver Program :: I DRIVE SAFELY
Just make sure they are CA approved. This particular one cost me $20. I'm not sure what the discount will be. Whatever "significant" mean. Check with your agent to see if it is worth it to you.