Good question!

It's easy to love the CM style of learning but then start to second guess things when standardized testing rolls around. I am happy to say that I have never supplemented anything for science (or for any other subject for that matter), and my ds has always had a 98% or 99% total score on his standardized testing each year.

With that being said, my dh and I have decided that first and foremost, the highest "score" our dc can have in life is to know and love the Lord. So, if they did just average in school, tested as average Joe's (as my dh says

), but still were happy and loved the Lord - we'd consider that a big success. HTH as you get ready to test! One other side note, we've done HOD all the way through. I think that is what has helped my dc do so well.
In Christ,
Julie