Kudos to your DD11 for her newfound organizational skills! I'm so proud of her.
She
owns this!
Internal locus of control.
Sometimes it's hard for parents to step back and just
appreciate the child who doesn't need them so much anymore... and begin to develop a different kind of relationship with them.
Keeping it together at school and then relaxing at home into total inattention?
Yes, it could be that, like many kids, she finds home to be her "soft place to land", unwind, de-stress, and process thoughts from her day.
On the other hand, your mention of la-la land and anxiety cause me to wonder: Is it possible that parenting style might be a contributing factor to any anxiety... and that DD11 copes by somewhat tuning out around you? Possibly it is time for the relationship to evolve a bit... each day, finding more things to compliment than to correct?