This post first appeared at RealClearEducation on April 1, 2014.

Our scientific understanding is always evolving, changing. Thus, one of the ongoing puzzles in education research is how confident one must be in a set of findings before one concludes it ought to be the basis of educational practice. If the data show that X is true, but X seems really peculiar, do we assume X is probably true, or do we assume that we just don't understand things very well yet? A new study provides something of an object lesson in this problem; in this case "X" was "parents teaching reading at home doesn't help much after kindergarten."

Here's the background on that counterintuitive finding. The work was inspired by the home literacy model (Senechal & LeFevre, 2000). It posits two dimensions of home literacy experience: formal experiences are those in which the parent focuses the child's attention on print, for example by teaching letters of the alphabet, or pointing out that two words look the same, or that we read from left to right.

Informal experiences are those for which print is present, but is not the focus of attention; reading aloud to one's child would be an example. Children usually look at pictures, not print, during a read-aloud.

Previous research from this research team, and others, has shown that formal and informal experiences have different effects. Formal experiences are associated with early literacy skills like knowing letters, and later, with word reading. Informal experiences, in contrast, are associated with growth in vocabulary and general knowledge.

But data supporting the home literacy model have usually been concurrent, not predictive, and have been limited to preschool, kindergarten, and early 1st grade. That is, the research shows an association between the relevant factors measured now, as opposed to showing that the home factors at, say, kindergarten, predict growth in reading outcomes for the 1st grade and beyond. That's peculiar.

There are at least two possible reasons. One is that the home literacy environment does have an impact on literacy growth, but researchers have been looking for the effect in 1st grade - just at the time that school instruction is so heavy. So perhaps the impact of home literacy environment on literacy growth is overwhelmed by the effect of school instruction. A second possible reason is that the home literacy environment may change as a consequence of how the parents perceive their child is doing in school.

A new study (Senechal & LeFevre, 2014) used a clever design to examine both possibilities. Subjects were 84 children in Quebec who spoke English at home, but for whom the language of instruction at school was French. So researchers could test progress in English, and thereby examine the impact of the home literacy environment independent of schooling. The research measured various aspects of children's literacy -- reading and oral language -- from kindergarten until spring of second grade. In addition, researchers used a number of measures to characterize their formal and informal literacy experiences at home.

The results provided strong support for the Home Literacy Model. Formal literacy activities at home were linked not only to performance in reading English, but, in contrast to prior work, a relationship was observed with growth in reading English from kindergarten to 1st Grade. Thus, there is some support of the idea that previous studies failed to observe the relationship because the experiences at school overwhelmed any effect that home experiences might have had.

But that can't be the whole story, because the relationship was no longer observed in 2nd grade. This is where parental responsiveness comes in. English instruction, one hour daily, began in 2nd grade, and so parents began to get feedback from schools about their child's English reading at that time.

Researchers found that the degree to which parents taught their children English at home was positively associated with student outcomes in kindergarten and 1st grade. But there was a negative association in 2nd grade. A straightforward interpretation is that many parents engaged in some English teaching at home during kindergarten and 1st grade, and the more of it they did, the better for their kids. Then in 2nd grade, parents get feedback from the school about their child's reading in English. If their child is doing well, parents ease off on the teaching at home. If their child is doing poorly, they increase reading. Indeed, researchers found that most parents -- 76 percent -- changed their formal literacy practices in response to their child's reading performance in 2nd grade. So you end up with a negative correlation of parental instruction and child performance in 2nd grade. The kids who are doing the worst in reading are the ones whose parents are teaching them the most.

The impact of informal literacy activities like read-alouds did not change; they were consistently linked to growth in vocabulary and other measures of oral language from kindergarten through second grade.

It should be noted that the parents in this study had greater than average education - more than half had a university degree. It's a good bet then, that the baseline home literacy environment was atypically high and that these parents may have been more responsive to their child's literacy outcomes than others would have been. We should not generalize these findings broadly.

Still, in this case, "X" turned out to be explicable and sensible. It appeared that parents teaching literacy at home did not help children's literacy because other variables had gone uncontrolled. This study doesn't solve the broader problem - we never know if our understanding of an issue is incomplete to the point of inaccuracy - but that's one issue on which we are at least closer to the truth. 

References:

Senechal, M., & LeFevre, J. (2002). Parental involvement in the development of children’s reading skill: A 5-year longitudinal study. Child Development, 73, 445–460.

Senechal M. & Lefevre, J. (in press). Continuity and change in the home literacy environment as predictors of growth in vocabulary and reading. Child Development.

If you follow education matters you know that the home environment in very early years are vital. One aspect of that home environment is the language infants and toddlers hear at home.

The groundbreaking work of Hart & Risley (1995; replicated by others, e.g. Huttenlocher et al, 2010) showed that socio-economic status of the parents is correlated with vast differences in the amount and complexity of language that children hear at home. 

But what aspect of this speech is important? Does speech need to be directed to children? Perhaps all that’s needed is for children to be in the presence of this more complex language. After all, we know that children do not learn language via instruction; they learn it by observation.

Three studies published in the last couple of years build a convincing case that parents should, indeed, talk to their children. Talking in the presence of their children (but to others) does not confer the same vocabulary benefit.

In the most recent study (Weisleder & Fernald, 2013), experimenters tested 29 Spanish-learning infants at age 19 months. The children wore a small device that made an audio recording of all speech to which the child was exposed. The audio recordings were analyzed by software meant to differentiate speech directed toward the child versus speech audible to the child, but directed to others. A subset of recordings was coded by human observers to ensure the accuracy of the software.

Recordings of a full day’s speech were analyzed and the results showed a huge range in child-directed speech; caregivers in one family spoke over 12,000 words to the child whereas in another family that figure was just 670 words. The amount of child-directed speech as not significantly correlated (r = .17) with the amount of overheard speech.

At 24 months the productive vocabulary of the children was measured by asking the parents to judge words that they believed their child understood and words that their child used.

Of greatest interest, the amount of child-directed speech at 19 months was correlated (r = .57) with vocabulary at 24 months. The amount of overheard speech at 19 months was not (r = .25).

The sample size in this study is limited and there were some quirky features. (E.g., the software sorting “child-directed” vs. overherd speech is good, but not perfect.) But my confidence in the conclusion is bolstered by reports of the same finding from another lab, investigating speakers of other languages: English (Schneidman et al, 2013) and Yucatec (Schneidman & Goldin-Meadow, 2012).

Why must speech be directed to the child?

Weisleder & Fernald administered another task at 19 months meant to measure word processing efficiency. They speculated that the effect of child-directed speech on vocabulary was mediated through efficiency—something like, for example, the speed and accuracy with which the particular phonemes of the child’s language are processed.

This doesn’t fully explain the difference between child-directed and overheard speech. The obvious hypothesis is that other cues (e.g. eye gaze direction) prompt greater attention to speech that is child-directed, and that attention is necessary to build efficiency.

More details will have to await further research. For now, we can say with greater confidence “talk to your children” not just “talk in the presence of your children.”

References

Hart, B. M., & Risley, T. R. (1995). Meaningful differences in the everyday experience of young American children. Baltimore, MD: Brookes.

Huttenlocher, J., Waterfall, H., Vasilyeva, M., Vevea, J., & Hedges, L. V. (2010). Sources of variability in children’s language growth. Cognitive Psychology, 61, 343–365.

Shneidman, L. A., Arroyo, M. E., Levine, S., & Goldin-Meadow, S. (2013). What counts as effective input for word learning? Journal of Child Language, 40, 672–686.

Shneidman, L. A., & Goldin-Meadow, S. (2012). Language input and acquisition in a Mayan village: How important is directed speech? Developmental Science, 15, 659–673.

Weisleder, A. & Fernald, A. (2013). Talking to children matters: Early language experience strengthens processing and builds vocabulary. Psychological Science, DOI: 10.1177/0956797613488145

Making a change to education that seems like a clear improvement is never easy. Or almost never.

Judith Harackiewicz and her colleagues have recently reported an intervention that is inexpensive, simple, and leads high school students to take more STEM courses.

The intervention had three parts, administered over 15-months when students were in the 10th and 11th grades. In October of 10th grade researchers mailed a brochure to each household titled Making Connections: Helping Your Teen Find Value in School. It described the connections between math, science, and daily life, and included ideas about how to discuss this topic with students.

In January of 11th grade a second brochure was sent. It covered similar ideas, but with different examples. Parents also received a letter that included the address of a password-protected website devised by researchers, which provided more information about STEM and daily life, as well as STEM careers.

In Spring of 11th grade, parents were asked to complete an online questionnaire about the website.

There were a total of 188 students in the study: half received this intervention, and the control group did not.

Students in the intervention group took more STEM courses during their last two years of high school (8.31 semesters) than control students (7.50) semesters.

This difference turned out to be entirely due to differences in elective, advanced courses, as shown in the figure below.

An important caveat about this study: all of the subjects are participating in the Wisconsin Study of Families and Work. This study began in 1990. when women were in their fifth month of pregnancy.

The first brochure that researchers sent to subjects included a letter thanking them for their ongoing participation in the longer study. Hence, subjects could reasonably conclude that the present study was part of the longer study.

That's worth bearing in mind because ordinary parents might not be so ready to read brochures mailed to them by strangers, nor to visit suggested websites.

But that's not a fatal flaw of the research. It just means that we can't necessarily count on random parents reading the materials with the same care.

To  me, the effect is still remarkable. To put it in perspective, researchers also measured the effect of parental education on taking STEM courses. As many other researchers have found, the kids of better-educated parents took more STEM courses. But the effect of the intervention was nearly as large as the effect of parental education!

Clearly, further work is necessary but this is an awfully promising start.

Harackiewicz, J. M, Rozek, C. S., Hulleman, C. S & Hyde, J. S. (in press). Helping parents to motivate adolescents in mathematics and science: An experimental test of a utility-value intervention. Psychological Science.