Test Hell and English Grammar

My son is in juken jigoku or “test hell” this year, as he prepares for his high school entrance exam next February. He goes to a special night school for three hours four nights a week where he studies the subjects that will be on the test, including math, Japanese history and English. While I can’t help him in the math department — at 15, he’s doing stuff that I can’t even identify, let alone solve — I am good at English, right? Well, maybe. I do my best, but the Japanese method of learning English for tests is so bizarre that I’m often not able to explain things to his satisfaction. For example, there might be a section asking the student to identify which of three infinitive verb constructions a group of sentences falls under, naturally with all grammar explanations done using complex terminology in Japanese, which he needs to master in order to pass, despite the fact that he can watch any mainstream Hollywood movie with 100% comprehension. As far as tests are concerned, English is treated more like a mathematical formula to solve rather than a living, breathing language for communication, and my attempts at explaining formal grammar to him often come up lacking.

I’m having difficulty teaching my son Japanese-style English grammar.