I was thinking about Khan Academy. The teacher recommended IXL, but I have read that kids get frustrated with the program because they get so close to moving on to the next level, answer one wrong, then are shot back down. Khan isn't so exciting, but it aligns with Common Core. DD11 needs a brief overview of the the math topics addressed this year, and it might do the trick. DD12 wanted to take an in person AoPS class, but it's at night during swim team. She expressed interest in the Alcumus program. She loved her last AoPS class.
