"We are not aware we are acquiring when we are acquiring, and after we acquire, we are not aware that anything has happened."

This is my favorite Krashen quote because it is at once both silly and correct. He's speaking of language acquisition. In Krashen's world, grammar drills have no use and explicit grammar correction no function. The only benefits would be seen on grammar tests, where the "monitor" can decide the grammiticality of a given item and correct it.

I recall beginning my ESL teaching in Micronesia with Betty Azar's black grammar book (a.k.a. the Black Betty). We filled and drilled, filled and drilled, etc. until the students could get a TOEFL score of above 470. (I was learning the grammar along with the students. It was quite interesting to me!) Then we would write essays and of course the students would not apply any information from the drills into the essays. I almost became a "But I told them the rule!" teacher. This sort of teacher blames the students, thinking that exposure to the grammar rule should automatically translate into success. No success? Show them the rule some more -- only louder! It's an exercise in frustration. (And we changed the classes a couple of years later, ditched the TOEFL and disowned the Azars -- not that it caused a great leap in student success, but at least we were teaching for communication rather than drills.)

Krashen's theory explains this experience and replaces the drills with "meaningful input."

The "Communicative Approach" which is now the hip model in ESL, and what I am trained in, is concerned with "meaningful output."

Somewhere there's a happy medium (she's probably talking to Elvis right now) -- what I like to call the "meaningful quantum revolving door of merry-go-round-put." In this theory the input goes in a revolving door, part of it decides to go grab a snack in the frontal lobe and the another part meets an old friend and goes back through the door as output. Thusly does acquisition occur.