We accidentally came across this little study that might be useful to some of you out there. Researchers found that different types of memory varied quite a bit throughout the life span - and not in a predictable bell curve fashion as one might expect.
Item memory is pretty similar at all ages, except for a little drop off by age 72, but look how kids age 7-10 have such an excellent sensitivity to color memory, but comparatively poor memory for location in space.
This is probably why color strategies work so well for spelling for this age group (also for young dyslexics). These students may remember the color sequence of letters and the letters they were associated with - easier than by location alone.
It's surprising how little strategic use of color is employed in conventional or computer-based teaching material. Usually color is applied in a gaudy fashion and without an deliberate plan, so the net outcome is distracting rather than informative.
Memory Strengths at Different Ages