'different learning styles'

This is a phrase that ed-school leftists seem quite enamored of.  What exactly does it mean?  What does it mean to say that inner-city youth aren't stupid, they simply have different 'learning styles' from suburban white and Asian kids.  I've never heard any specifics as to how these people's 'learning style' differs from that of other people.  Moreover, I've never heard any indication that this different 'learning style,' whatever it is, is remotely as effective as that of other people.  If the only difference between one 'learning style' and another is that one is more effective than the other, you should simply ditch the ineffective one, n'est ce pas?