Memorize the vocabulary?

I received this email:

I have a couple questions for you.

My son is only completing the exercise you give for homework.

He’s not learning vocabulary or grammar rules.

My daughters are always meticulous with Latin writing everything down. They do pretty well in Latin.

Should I require him to do more written work in order to learn this more thoroughly?

Also, during class I think he needs to be typing in his answers for most questions you ask. Is this correct?

Here is my reply:

We are definitely covering grammar in class.  If he is paying close attention, he is getting it.  I have spent years developing the clearest explanations I can for each grammatical concept.  When it comes to grammar, he may be fine.

As for the vocabulary, I am not sure how to answer.  When it comes to Latin, I march to a distinctly different drummer.  Most teachers will tell students to memorize the vocabulary.  I tell them to keep either of these sites available at all times.

I am teaching myself Greek.  I have nothing like these sites available for Greek.  Still, I don’t really bother memorizing the Greek words.  Every time I encounter a word I do not know, I look it up in a physical dictionary.  Time-consuming, for sure.  And yet, I find that I am slowly learning Greek vocabulary.  The more I read, the more I learn. 

I sometimes think all the flashcards, quizzes, lists, and games are not so much to help students, but rather an attempt by teachers to sell products.  No way I can prove that of course.  Just my suspicion.