Mickle and muckle.

I would like to shoot the teacher who taught his class this line:
"Many a mickle make a muckle".
The student used this when trying to say "Practice makes perfect".

A little research would have shown the teacher that "Many a little makes a mickle" goes back to the 17th century, and is now obsolete.

This is all in the context of the Hong Kong Examinations & Assessment Authority expecting Form 6 students to be able to use a wide vocabulary during their written and oral exams. The teachers tell their students to use big words, but don't explain the difference between a big vocabulary and a strong vocabulary.

In my not-so-humble opinion:
A vocabulary is the number of words of a certain language that you know.
A big vocabulary means you know a lot of words.
A strong vocabulary means you know how and when to use certain words.

Mickle and muckle make for inappropriate vocabulary that is used in an attempt to impress the examiners.

http://www.phrases.org.uk/meanings/many-a-little-makes-a-mickle.html