I went to an all girls cath. high school, and I really liked it, I had a few good friends and everyone was pretty nice. It was considered a very academically rigorous school, but after hearing about the school my dh attended, also catholic, I think the girls' school could have done more, created more opportunities for additional challenge. That was probably the only drawback and I imagine/hope you could work with a school on getting additional challenge as needed.
I do recall getting some good advice from one of the nuns teaching french; I asked what I could do to improve my grade in that class and she just said, "Well, you could consider studying."

We had an outstanding teacher for physics, the only male teacher that I recall. He was a retired Air Force Colonel, he was just fantastic with the subject and as a person. Of course there were several outstanding female teachers as well, some nuns some regular folks. Good school; it is unfortunately closed now.