I think you need to start with asking yourself why you brought her home in the first place?
We all go through periods of doubt with our "abilities" but I am convinced that parents ARE the best teachers for their kids. I think you're on the right track with trying to teach independence, but like anything else in life, she has to learn that there are consequences. Will she have to take tests at the end of the semester and/or year? Just doing the bare minimum won't cut it and she may have to learn the hard way. Can you sit down and discuss this with her, and set some guidelines and clear penalties for not doing the job properly?
We've had our kids in the public schools but they're home now and I'm personally very anti-public school, so I'm not the best person to give unbiased advice!

But if this were the direction you decided to pursue, as I said in the beginning, what made you take her out in the first place? Remember kids learn to "cheat the system" in the public schools all the time!! That won't necessarily solve this.
All families work differently, but I know in our home, if this type of thing were happening, we would step back from the "academics" for a while and address the deeper issue of why she's doing this. Is she burned out on the curriculum? If your state requirements aren't all that strict, let her pursue something
she's interested in for a while! It's amazing how much information a child can absorb when they're learning about something they truly want to know (my DS12 is a gear-head, so any time he can take apart a small engine or help his dad on the van, he's in adolescent-boy heaven!).
I'll quit here because I feel like I'm just rambling now, but those are some thoughts FWIW! Hopefully some others here will chime in with their experiences too.
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