I went to a RC school as a non catholic. My sons (eldest is catholic youngest not), attend catholic schools.
We only said a prayer during whole schools assemblies once a week and year assemblies once a week.
Had two hourly RE lessons per week.
Advent and lent would be a whole school mass for one hour
We had 2 nuns teaching (RE and Science). They were brilliant- intelligent, funny and down to earth individuals (remember once people were talking about someone had sex with someone else, and one sister turned around and said 'I heard that, I hope they were sensible and used contraception!'
We had a small chapel which our weekly year assemblies were held in
This was a statue of Jesus on the crucifix in our school hall.
We had sex education, were told the importance of using contraception etc.
That was the amount of 'catholicism' I saw and experienced in my RC high school.
I asked my dc about it now, and they have confirmed that minus the teaching nuns, it's still the same.
They don't do prayers everyday, mass is only at important events and during RE they regularly discuss others religions, and have been told to respect others beliefs and that just because they are Catholic (obviously my youngest isn't), it does not been other beliefs are wrong.
Our high school is always over subscribed because it is the top performing school in the county. There is also a lot of children who attend who are not catholic. The main difference for me and my youngest was going up for communion during mass and crossing our arms instead of accepting bread. (Although ds has accepted bread because he wanted to see what it was like
).
So I would seriously say to people who may be thinking about a RC school, to visit, and talk to the students. I can only say what happens at our school, from pp it's apparent that some schools do prayers several times a day etc. So check it out, they aren't all the same. You may be surprised.