If they are pattern based and looking for big picture then brute force memorization probably is not going to get it done. Learning multiplication tables through understanding patterns is going to be much, much easier. Of course there is also a somewhat independent of intelligence bit of the brain wiring that affects a person's general sense of numeracy.
I'd suggest this PDF as a technique to try (also a number of threads here going through the same question)...
http://www.visual-learners.com/support-files/nbf-6-9-10.pdf
