My ex hated me doing anything learning related with the kids - reading, kids and cat all snuggled up to listen, letting them have classical music on at night, showing them anything about animals, plants or wildlife, any slightly disguised maths activities, absolutely hated it.
He genuinely appeared to believe that by reading to them, I was stopping them from magically working out what words meant from looking at the pictures. There was also some wittering about me being really big headed if I thought I could do better than a teacher in school and how common/lower class/weird it was to spend time in a child's bedroom just so I could brag about them being able to read instead of spending the time cleaning the kitchen or watching soap operas.
I did wonder whether there was some sort of trauma as I knew his father had seen home learning as best reinforced through the medium of physical violence, but in the end, as he'd suddenly flipped from appearing to be a relatively normal person when DD was born and one day took it upon himself to smash up my bookcase and literally burn my books as they 'are only there to show off', I settled upon Being an Utter Prick as the most appropriate explanation.
I'm pretty certain that had he found somebody else stupid enough to have a kid with him, they'd have arrived at school having never seen a book.