Bloom’s “Taxonomy of Learning” was only half of his most impactful education research
Relatively little is known of the other cornerstone of his research: The 2-Sigma Problem.
In his Taxonomy of Learning, Bloom organized the whole universe of cognitive tasks into steps on an increasingly complex pyramid. As the eye scans to the top of the pyramid, the cognitive load placed on students increases.
The most common application of this research is to increase the rigor in our classrooms.
Bloom argued that teachers (and the standards that guide their instruction) should not rely on students knowing concepts alone. Churning out hoards of students who simply know things builds a society of really good Jeopardy players but really bad policy thinkers, engineers, entrepreneurs, etc.
Bloom’s Taxonomy is a valid and universally accepted ideal. You can overhear teachers and school leaders talking about “Bloom’s,” “higher-level thinking,” and “depth of knowledge” in virtually any PD. Infographics depicting Bloom’s famous pyramid adorn the walls of more than a few classrooms. Bloom’s Taxonomy is a huge, famous idea that has hugely, famously gained traction.
The 2-Sigma Effect
Yet Benjamin Bloom brought another, perhaps more powerful sonic boom to the education world, and it’s called The 2-Sigma Problem. It sounds like a bad Wesley Snipes feature, but 2-Sigma is actually one of the foundations of the achievement gap.
And it’s a problem our generation desperately needs to solve.
Benjamin Bloom’s oft-forgotten 1984 study concluded that students who were tutored (either 1:1 or in small groups) outperformed 98% of their non-tutored peers. This outperformance was equivalent to 2 standard deviations, hence the sci-fi name.
Furthermore, 90% of tutored students reached the same level of summative achievement as the top 20% of students in traditional classrooms. This quantum leap in student performance has since been confirmed in a swarm of academic studies.
Tutoring works, particularly when it is paired with a mastery approach in schools.
The 2-Sigma Problem
Why is this a problem? Well, tutoring — no matter how effective it is — is also very expensive.
Because of the steep cost, tutoring simply wasn’t a viable option for the types of schools that were in dire need of the results tutoring could provide. As a result, tutoring was an “elite sport” like golf: only the rich could participate.
This has the effect of widening the achievement gap. So Benjamin Bloom posed The 2-Sigma Problem to the education community:
find or invent a model that achieves the same impact as 1:1 and small group tutoring, with a cost that doesn’t exclude schools and communities that could really benefit from that impact.
Members of the education community at large — whether they know they’re doing so or not — have have been trying to find the solution to this problem for decades. From adaptive software approaches to school choice vouchers, education advocates from every corner of the market have posed solutions to Bloom’s 2-Sigma problem.
And all have failed. All but one.
2-Sigma in practice
Over time, policy thinkers who took note of Bloom’s research concluded: “If you can’t beat ’em, join ‘em.” If we can’t solve The 2-Sigma Problem with some novel approach, they figured, why not just tutor everybody?
They tried to scale tutoring nationwide.
In the early 2000s, as part of the No Child Left Behind act, federal and state governments shifted huge sums of money into programs that provided Supplementary Education Services (“SES”) such as after-school enrichment hours and tutoring programs.
These SES policies sought to put Bloom’s 2-Sigma research to work for our our nation’s most vulnerable students.
There were huge positive effects of tutoring in various schools under NCLB. Researchers have confirmed this.
But, as with many education initiatives involving lots of money, things quickly got hairy for NCLB tutoring programs. Sadly, the well-intentioned path to education reform in the 2000s was paved with poor execution.
It was hard to measure the impact of each tutoring program with such a swarm of disparate initiatives coming to bear. As the accountability measures for SES programs weren’t fully hammered out, SES tutoring providers ripped schools off with impunity. In awarding lucrative tutoring contracts, nepotism also became standard practice.
It was the Wild West out there! Soon, tutors started missing work, and schools scrambled to replace them. Of course, consulting firms peddling the various SES programs walked away with truckloads of taxpayer cash as the system crumbled.
This was, without a doubt, a massive failure to deliver on a massive promise.
But I see this failure in different terms. I see this as the whole system running headlong into something Bloom warned us about 20 years earlier: tutoring works, but it can’t be scaled because of cost. The 2-Sigma Problem!
End of story, right?
No. We have a solution to 2-Sigma.
At Zeal, we have spent 5 years building and executing the world’s first successful solution to Benjamin Bloom’s 2-Sigma problem.
We deliver the same results as in-person 1:1 tutoring at 1/50th the cost. And we have accomplished this with nearly 50,000 students so far.
How? We use technology (an amazing assessment matrix of 30,000 math items) to assess K-12 students on grade level math skills from their classes. Then, we adapt each child to an appropriately challenging level within those skills — this is the idea of the zone of proximal development in practice. Finally, we deliver live, human tutors who help shore up students’ learning gaps.
We do this all during a standard math block, once or twice a week.
At the end of a school year, Zeal students have each learned the equivalent of an additional half year of math relative to their peers.
High-impact tutoring can be done at scale. We do it everyday at www.zeal.com
To learn more or see how tutoring on steroids would impact your students, send us a note at partners@zeal.com