Anonymous wrote:Khan Academy
free and she can work at her own pace
https://www.khanacademy.org/science/chemistry
This!
Khan is intended to cover the full breadth but not dive in too deeply.
I would suggest that she focus on understanding each unit before progressing to the next and spend as much time as necessary on balancing equations (unit 4 in khan), using as many worksheets as necessary to make sure she is consistently able to do it. In my experience, balancing equations requires more time for some students than a chem class allows, and it's foundational to stoichiometry (unit 5) and the rest.