Welcome on the board.
You have quite a challenging situation on your hands. We will hs next year as well, but unlike you I have the option of going to museums, have DS5 (YS) take outside classes, enjoy the sports, which all makes a huge difference. Even as it is I worry that we will end up spending too much time together.
I too would suggest trying interactive classes over the Internet. If money is an issue may be Davidson could help. I believe they could help you find a mentor for your daughters.
I hope your house will get selected for the home makeover. Good luck.
