Years ago I was concerned about this and made a plan with my wife for what to do if she was at work.
But now we have a bunch of kids in different schools and haven't updated our plan.
Does anyone have a plan for what happens if we have a really bad event?
Pray for clear skies and go out and watch the beautiful aurora, silly!
Depending on the kids' ages, you can teach them quite a lot about the Earth's magnetic field and why the aurora concentrates at the poles, how the high-energy particles light up the sky (it's a lot like a neon light), and how the atmosphere shields us from any danger despite the spectacular show.
For a really bad event that managed to blow a lot of transformers (presumably due to grid operators not seeing it coming) ... well, take up farming.
First rule of fight club...
Keep a couple days water and food on hand, go up to the pub, have a pint, and wait for this all to blow over.
A really bad event would be that long-distance transmission lines act like antennas and pick up millions of volts and blow up all the transformers.
I don't know how much you can plan for that other than "if it happens, try to get home", and then all the usual prepper stuff.