I agree with Nan. If she loves science and is willing to put in the hard work, I would let her interests soar by switching into that class. It seems to me that the guidance counselor gave her faulty advice. There could be another huge benefit: she could love what she learns in that class!
Speaking for myself, I know it's easy to get into mom-worry about grades, but colleges look at the difficulty of course loads. I will have to hold myself back not to lead my children into doing what I did, which was worry more about my transcript/resume than focus on what truly interested and challenged me.
