Bloom's Landmark Study on the Benefits of One-to-One Instruction

Benjamin Bloom empirically proved the achievement benefits of one-to-one instruction over the conventional classroom in 1984. 90% of students receiving one-to-one instruction tested in the 20% of student who learned in conventional classroom settings. Calling it the "Two Sigma Problem," he lamented that "most students do have the ability to reach this high level of learning" but that individualized instruction is "too costly for most societies to bear."

mike gervits