Understanding the Achievement Gap

What is the "achievement gap"
and how does it form?

The term "achievement gap" originated in the 1960s, when researchers began studying the disparity in academic performance between groups of students. As Education Week explains it:

“The achievement gap shows up in grades, standardized-test scores, course selection, dropout rates, and college-completion rates, among other success measures."

Historically, researchers used the term to understand differences in academic outcomes between students of different races, but lately, research has shown that achievement gaps are now growing fastest between students of different income levels. In 2012, the New York Times reported that while the achievement gap between black and white students has shrunk since the 1960s, the achievement gap between low and high-income families has grown by 40 percent.

Differences in children’s academic and social skills are observable as early as kindergarten. That's because children experience a period of rapid development during their first few years of life. Between the ages of 0-3, children's brains develop more than 1 million neural connections every second, according to the Harvard Center on the Developing Child.

During those early years, experiences shape a child’s development. In particular, the way that adult caregivers respond to a child shapes the child’s brain architecture. As the Harvard Center on the Developing Child explains it:

“When an infant or young child babbles, gestures, or cries, and an adult responds appropriately with eye contact, words, or a hug, neural connections are built and strengthened in the child’s brain that support the development of communication and social skills. Much like a lively game of tennis, volleyball, or Ping-Pong, this back-and-forth is both fun and capacity-building. When caregivers are sensitive and responsive to a young child’s signals and needs, they provide an environment rich in “serve and return” experiences.”

How do we promote equity? Early talk is the key.

These serve and return interactions can take many forms. At LENA, we focus on interactive talk between children and caregivers. Interactive talk — also known as “conversational turns” — occur when a child and caregiver respond back-and-forth to each other.

For many reasons, children experience significantly variable levels of interactive talk with adults. In 1995, researchers Betty Hart and Todd Risley found that children from lower-talk homes heard 30 million fewer words than children from higher-talk homes.

Follow-up studies using LENA technology have confirmed a “talk gap” that’s correlated with socioeconomic status — commonly referred to as the “30 million word gap” — which may appear as early as 18 months of age. (LENA data show that the average difference may be about four million words, but the differences grow to 30 million words when looking at the wings of the normative distribution.)

Data from a sample of hundreds of families show that these differences in talk levels are correlated with socioeconomic status. However, looking solely at how much money a family makes is not a sufficient predictor of how much they talk with their children — there’s large and documented variability within different income groups. Even in the same household, talk levels vary significantly during the course of the day and from week to week. Regardless of the exact number though, the key takeaway is that there is a significant amount of variability in children’s language environments, and that it matters for child outcomes.

Studies since Hart and Risley's first, earliest “30 million word gap” findings increasingly point to conversational turns, rather than adult words alone, as the key brain-building ingredient. Because of this new research, we avoid using the term "30 million word gap," as it has increasingly become insufficient to capture the complexities of the early talk gap, which is more about quality than quantity.

To understand why differences in the amount of conversation children experience matter, it’s necessary to understand how interactive talk shapes a child’s brain. Research shows that the language a child experiences is related to:

Additionally, research tells us that a child's vocabulary at age three predicts language and reading skills at ages 9-10, about the time they're finishing third grade. In turn, third grade reading scores strongly predict high school graduation.

When taken together, these studies indicate that a person’s early language exposure is a good indicator of their future developmental trajectory.

Inspired by this research, LENA's founder Terry Paul created the LENA device as a means of giving parents, teachers, and caregivers objective feedback on exactly how much they talk with children. Just like with healthy food, this “language nutrition” benefits every child, regardless of their background.

Now, Terry’s vision is increasingly becoming a reality: LENA partner sites across the country are implementing the technology as part of programs focused on closing opportunity gaps by boosting early language. Aggregated results show that relative to where they started, children whose parents or teachers participated in LENA programs are experiencing more brain-building interactions, particularly those who started the programs experiencing the least amount of talk. Children whose parents participate in the LENA Start program are gaining nearly two months of developmental skill every month. Longer-term, a
longitudinal evaluation from Huntsville City Schools in Alabama looked at the school readiness of 4-year-olds whose families had participated in LENA Start an average of 2.5 years prior, finding that the children demonstrated considerably higher early literacy scores than a matched control sample.

By teaching caregivers about the importance of interactive talk and equipping them with practical strategies to increase conversations every day, our mission is to close the "early talk gap" for good.


2018: The Year of the Conversational Turn

In 2018, researchers published three important studies on how
conversational turns in early childhood are related to brain activity, brain structure, and IQ in adolescence.

Learn more

Proving the Power of Talk: 10 Years of Research on the Impact of Language on Young Children

The past decade was seen widespread acceptance that early language plays a critical role in babies' brain growth and in their subsequent success in school and in life. Read a summary of the latest research on the power of early talk!