Concrete first, abstract later

"From a pedagogical point of view, there is no doubt that for most students, concrete examples should precede abstraction"

That is a simple but yet meaningful phrase that I liked and took out of David Poole's book named Linear Algebra, A Modern Introduction.

I wish most teachers and professors would adopt that approach in class, what truly connects students with conceivable day-to-day sense, than move on to abstract areas of understanding.