Teachers regularly report that they have more skills to teach students than the time necessary to teach them. Therefore, teaching often requires making tough choices about which skills to focus on and which to minimize or skip entirely. How do teachers decide which skills to teach?

In resolving this tension, Lemov, Woolway, and Yezzi (2012) suggest guidance from “the 80/20 rule” or the “law of the vital few.” They note that this is “a pattern that holds true again and again” and that in many endeavors, “80 percent of results turn out to come from 20 percent of the skills you learn.” With this in mind, they assert that educators should identify and focus most intently on “the 20 percent of things that most create value” rather “than the other 80 percent of things [they] could plausibly spend time on” (Lemov, Woolway, and Yezzi, 2012).

“80 percent of results turn out to come from 20 percent of the skills you learn.” – Lemov, Woolway, and Yezzi (2012)

A clear example comes from mathematics. Basic math facts would clearly qualify as part of the “20 percent” or “vital few.” When they are well known, all other studies in mathematics are facilitated. When they have not been mastered, everything else is encumbered.

However, the “law of the vital few” is simply a theory. Can we test its validity?

Work in the emerging area of learning progressions often includes the identification of essential skills that are necessary prerequisites for subsequent ones, sometimes referred to as “focus skills.” Might an expert review of standards confirm or refute the law of the vital few?

Consider work done by the National Foundation for Educational Research (NFER) in developing a learning progression for the national curriculum of England as profiled in Kirkup et al. (2014). Their detailed analysis of the entire mathematics curriculum revealed 1,000 specific teachable skills across all years of school. Of these 1,000 skills, 30% were identified as focus skills. In reading, 1,100 overall skills were identified, with only 29% of those being noted as focus skills.

In the United States, Renaissance^® has undertaken similar analyses of learning progressions based on both the Common Core State Standards and the standards of non-adopting states (Alaska, Nebraska, Oklahoma, Texas, and Virginia). Across all these analyses, it is clear that a minority of skills represents the most significant prerequisites for other skills. The assertion that this minority represents 20%, however, appears to be a low estimate. Though they vary from a low of 29% to a high of 42%, most standards sets contain about 30–35% focus skills.

“Across all these analyses, it is clear that a minority of skills represents the most significant prerequisites for other skills.”

For Renaissance customers, focus skills are clearly identified in reports and dashboards in Renaissance Star Assessments^®. This information is helpful to teachers as they attempt to prioritize their efforts with students. For customers without access to Star solutions, Lemov, Woolway, and Yezzi (2012) suggest that when in doubt, we can “consider harnessing the wisdom of crowds” by “[assembling] a group of relatively informed people and [asking] them to name the top five. Using the top five cited ideas as your answer won’t be perfect, but it will be darned good.”