Rav Avigdor Miller on Sending Your Son to High School Lisheim Shamayim
Q:
Should one send his son to the English classes in high school? Don’t they teach apikorsis there?

A:
And the answer is that they do. And that’s why it’s a very important question you’re asking.

First, there’s a separate question: Should your children learn the language of the land? And the answer to that question is yes. It’s valuable because a person should teach his son an umnus, a trade. It’s a gemara that a man should teach his son to make a living. And even though we don’t know what he’s going to do, but he’ll have to know how to read and write and calculate; so he’s going to need a certain amount of education.

Now, I’m not saying that if a person wants to send his son to a place where there’s no limudei chol, that he’s doing something wrong. But the people who are sending their children to limudei chol, if they’re doing it lisheim shamayim, they should know that it’s a good thing too; no question about it. You have to make a living in this world. You have to support a wife and children. And therefore when a young man has some kind of a preparation, so it’s like teaching him an umnus.

However, the problem that you mentioned of teaching apikorsis, that’s a very important problem, and you have to be very careful. And therefore in some yeshivos they have a hashgacha on what the teachers are saying, and you can rely on them.