Unfortunately, many Catholic schools in the UK today are only Catholic by name. There are some independent (private) Catholic schools where the Governors have more authority to decide on matters such as religious syllabus and discipline, but the majority of schools are state schools.
It’s something of a generalisation, but a lot depends on the location of the school and the type of neighbourhood it is in. For years there has been a very counter-productive agenda that seems to resist encouraging pupils from less wealthy backgrounds from striving to be achieve or confronting anti-social behaviour in the classroom. I think the observation in a previous post about children sitting in orderly rows, wearing the correct uniform and treating school as a place to learn self-discipline as well as academic work says it all

Those were the days when social mobility was a reality and children from poorer neighbourhoods had the chance to learn and achieve. In the UK, we’ve lost that ethos in many schools.
My nephew is currently at a primary (aged 4 to 11) Catholic school in the UK. He’s recently made his First Communion, Confession and been Confirmed. He’s the only child in his school who regularly attands Mass at the Parish church. He went through a stage of not wanting to go to Mass, saying it was ‘boring’ and proclaiming that going to Mass on a Sunday wasn’t really important, because some people could act holy on a Sunday and be awful during the week and it was more important to be a good person.
We explained to him that this was a false choice: that listening to the readings and taking part in the Mass properly helps one to be a good person and should inspire one’s acts of kindness outside Mass.
“Oh no!” he said, “Mass isn’t important. People who do good deeds outside Mass are better!”
So, we asked him about receiving the Eucharist now he’d made his 1st Communion and how impoertant it was to be able to receive the Body of Christ.
“Oh no! That’s not actually true! It can’t really be the Body of Christ! Nobody believes that: it just represents the Body of Christ and it doesn’t matter if you have it every Sunday or not!”

We asked him where this information came from and he named his class teacher! Incidentally, my mother went to one of his Sacramental Preparation classes with him and said there was absolutely no mention of Catholic doctrine. It was all ‘woolly’ stuff about being nice. There wasn’t one mention of what the Sacraments actually meant.
When I mentioned this to some teachers in the parish who teach at a different school, I was told it was okay to teach that sort of ideology because they didn’t want to ‘offend’ anyone whose parents didn’t attend Mass. I countered that if one sent one’s child to a Catholic school, one had made the choice to have their child exposed to Catholic teaching - sacraments and all. This was met with horror! What about all the non-Catholic and lapsed Catholics who send their children to the school? If they went, how would the school survive?

I am sure the school would survive and thrive if the discipline and quality of teaching was such that it attracted more pupils. Right now in the UK, the system of inspecting and grading schools means that a school can only be ‘Outstanding’ if it promotes secular values and ‘learning by choice’
If I was not in a position to afford an independent Catholic school, I would look for the best available primary school, regardless of denomination.