As my Greek students know, I have spent a good bit of time studying how the memory works and how to better remember things like vocabulary for Greek, Hebrew, German, French, and a few other languages I have studied. One of the great things about NT Greek is that we have a closed corpus. That is, we know exactly what books the student will be reading in Greek and can focus on the vocabulary for those books alone. When a student is learning classical Greek, for example, one cannot do this because the list of books to be read is very large.
With the NT we know that there are around 5,430 different words in the NT (give or take a few) and that these words occur a total of around 138,000 times. We also know that of those 5,400 words there are only about 315 that occur more than 50 times. So a student can learn all the words that occur more than fifty times in the NT and manage to read the NT with a lexicon. I teach my students that it is almost counterproductive to learn words that occur less than about 25 times.
For a list of these words and a wonderful online tool for learning them check out http://wermuthsgreekbook.wordpress.com/2008/03/06/58/ This is a web page by a friend of mine named Robert Wermuth. He blogs about ancient Greek, a very exciting subject I can assure you, and has written a fine book on learning the paradigms for first year students.
Check out his page, his PDF of all the words that occur more than ten times, and his program for testing yourself with these words. If you are a Greek student you will be glad that you did.
Onward to greater exegesis . . .
DrSamLam