lgm on algebra in 8th grade

Comment left by lgm:

My college has shown statistics to interested alumni that say doing well in 8th grade algebra correlates with being successful in Calculus AB, which correlates to being most successful in earning an engineering degree in four years as opposed to dropping out or taking five/six years.

The "brain rule" that the brain needs 10 years to consolidate a memory comes as earth shattering news to me. Of course, I'd known about the 10-year rule for some time:

Some evidence that a great deal of practice, and not just talent, is a prerequisite for expertise is the "ten year rule," which states that individuals must practice intensively for at least 10 years before they are ready to make a substantive contribution to their field. What about prodigies like Mozart, who began composing at the age of six? Prodigies are very advanced for their age, but their contributions to their respective fields as children are widely considered to be ordinary. It is not until they are older (and have practiced more) that they achieve the works for which they are known.

Practice Makes Perfect -- But Only If You Practice Beyond the Point of Perfection
by Daniel Willingham
American Educator, Spring 2004

But it hadn't occurred to me that memory per se -- memory for ordinary, everyday skills and knowledge, as opposed to the memory involved in expert performance -- might also require 10 years to gel.

I am completely blown away by this.

Assuming John Medina is citing a field of research separate from the research on expertise (I'll find out when my copy of his book arrives), I'd say we have converging lines of evidence both for the 10-year rule and for assuming a causal rather than merely correlational relationship between algebra in the 8th grade, success in AP Calculus AB, and obtaining an engineering degree in four years as opposed to 5 or 6.

The fact that constructivist curricula are slower than the semi-traditional curricula they replaced is horrifying.