kitchen table math, the sequel: rule of 20

## Thursday, September 9, 2010

### rule of 20

Surprisingly, the vast majority of skills which we try to teach appear to begin the passage from acquisition to fluency-building at roughly the same point —when correct frequencies are somewhere between 14 and 20 per minute, and an accuracy of between 67% and 83% has been achieved. That rule seems to apply to very basic behaviors like pointing to named objects, steps taken while walking, and completing parts of a dressing sequence. The same transition point also seems to apply to very complex behaviors like reading, speaking, and writing digits to solve advanced mathematics problems. Indeed, the rule appears so universal that when Sokolove (note 9) examined circa 3300 programs of children in grades 1 through 6, the “rule of 20” predicted progress in more than 97% of the cases.

Decisions, Decisions
Owen Roberts White
University of Washington
Fall 2000

LynnG said...

I'm going to have to test this theory on my 10-year old. She's the only one handy to use as a guinea pig for this sort of thing.

Jennie said...

White's article deserves a thorough read. It's a fabulous introduction to Precision Teaching, and it's is a great addition to anyone's reference list regarding instruction and learning.

Catherine Johnson said...

Jennie - thanks for the tip.

Just stumbling across the 'rule of 20' was fantastically helpful for me.

Today I had my composition class do a one-minute timed worksheet of its/it's distinctions - and what a revelation.

The fastest student got through 14; the slowest through 4.

I did 20 - which was the most I could do while writing the word 'its' or 'it's' out in full (which I think they should do --- ??)

Now I'm thinking that for students who were around 4 I should create much simpler worksheets using phrases instead of sentences.

Of course, I also don't know how fast or slow their handwriting is.

Anonymous said...

I haven't read the article (yet), but do they provide a reasonable definition of the skills to which this rule-of-thumb applies?

I'm pretty sure that it won't work if the skill is "repairing an automobile transmission" or "write a computer program that does ___." Maybe repairing a transmission isn't a skill the way the word is being used here?

-Mark R.