The adage, often misattributed to Einstein, that “education is what remains after one has forgotten what one has learned in school,” implies that forgetting is a significant part of the learning process. But how much do students actually forget, and how quickly does it happen? Research suggests that forgetting may be less pervasive than we think, and that under certain conditions, memories of learned material can last a lifetime.
The Forgetting Curve: Not as Steep as You Think
Numerous studies have explored how much students retain after initial learning. These studies often involve testing students on material learned in a course, then retesting them after a delay. While forgetting does occur, the rate is often slower than expected. A review of such studies found that, on average, students retained about 72% of information requiring recall (e.g., short answer questions) and 84% of information requiring recognition (e.g., multiple-choice questions) after a significant period.
Factors Influencing Knowledge Retention
Several factors influence how much and how fast students forget:
Time Elapsed:
The longer the time since initial learning, the more likely forgetting is to occur. However, research shows that after an initial period of rapid forgetting, retention levels often stabilize.
Initial Learning Strength:
Students who master material initially tend to retain it better over time. A strong foundation of understanding creates a more resilient memory trace.
Subsequent Review and Application:
Revisiting learned material, either through review or application in new contexts, significantly strengthens memory. Students who use learned information in subsequent courses or real-world situations are less likely to forget it. For example, physics students retain mechanics concepts better than biology students because they continue to use them.
The Power of Relearning and Savings
Even when information seems lost to conscious recall, it may still be present in memory in a latent form. This is demonstrated by the phenomenon of “savings in relearning.” When re-exposed to previously learned material, even if seemingly forgotten, students relearn it much faster than they did initially. This suggests that some memory trace remains, facilitating faster re-acquisition.
Why We Overestimate Forgetting
We often overestimate how much we’ve forgotten due to:
Retrieval Failure:
Mistaking an inability to immediately recall information for its complete absence. Persistent effort to retrieve a memory often leads to success.
Loss of Context:
Remembering the content of learned information but forgetting the source (i.e., where and when it was learned). We might know a fact but not recall learning it in school.
Does What We Remember from School Matter?
Research suggests that formal education does make individuals smarter, likely due to the accumulation and retention of knowledge. Studies have linked years of schooling with higher IQ scores, even after controlling for other factors like socioeconomic background. While the exact mechanisms are still being investigated, evidence points to the importance of content knowledge in boosting cognitive abilities. The breadth and depth of knowledge acquired in school, and the ability to apply that knowledge, contribute to overall intelligence.
Conclusion: The Lasting Impact of Learning
While forgetting is a natural part of the memory process, students retain more of what they learn in school than is commonly believed. Factors like initial learning strength, subsequent review, and application play a crucial role in long-term retention. Even seemingly forgotten knowledge can be quickly relearned, highlighting the lasting impact of formal education on cognitive abilities. Rather than viewing education as what remains after forgetting, it’s more accurate to see it as the accumulated knowledge and skills that persist, shaping our understanding of the world and contributing to lifelong learning.
