Loudoun County Libraries offers several resources that are free of charge.
They are currently offering their online learning hub. There is even an option for live tutoring for grades kindergarten and up (2:00 pm - 11:00 pm), a 24 hour writing lab, and foreign language lab/Spanish speaking support, plus much more.
A library card is needed for the live homework help. Sign up here online or visit a branch.
Here is the link for the main page: