At my primary school in the 50s we had assembly everyday. We sat crossed legged on the floor in long rows. There were 41 in a class from ages ran from 5 to 11.
Also in the C of E secondary modern school I attended 3 classes in each year, assembly was held every morning, crossed legged on the floor, except for Thursdays (I think) when we all went to church, instead of first class. There was a RE class every week.
My 3 DDs all went to a French RC, although a religious school there were no daily assemblies, only two church services, one at the beginning of the school year, the other at the end, not even at Christmas one. However, because it was a church school they also had a weekly RE. class, but they also learnt about other religions.