Making Inferences in Reading Requires Background Knowledge


For much of my career as an educator, I have been barking up the wrong tree in trying to develop successful readers, overestimating the importance of reading “skills” and underestimating the importance of knowledge.

In my article “How Knowledge Powers Reading” in this month’s issue of issue of Educational Leadership I’ve written about what teachers can do about it if they believe, like me, that there’s low value in reminding kids that “an inference combines what we already know with cues in the text,” and that a much better way to increase students’ ability to combine what they already know with cues in the text is to increase how much they already know.

I thought I’d share an example of this from an experience I had while reading with my youngest daughter.

We were tucked in a few nights ago reading aloud from Laura Ingalls Wilder’s On the Banks of Plum Creek. We came upon a scene in which Laura’s parents announce one winter evening that the family is going into town, for reasons that they at first keep from Laura.

“But why. . .” asked Laura. “Why are we going to town at night?”

“It’s a surprise,” said Ma. “Now no more questions. We must all take baths and be our very nicest.”

In the middle of the week, Ma brought in the washtub and heated water for Mary’s bath, then again for Laura’s bath and again for Carrie’s.

The phrasein the middle of the weekis hugely important here because it expresses how unusual and exciting this all is for the children–what a special and rare happening is afoot. Later, it turns out that they’re going to attend Christmas services–a big deal to them. But there was no way for my daughter to make that inference about the specialness of family’s planned excursion, and it wasn’t because she lacked “reading skills.”

First, here’s what you’re supposed to understand: Families like Laura’s, living on the Western frontier in the second half of the 1800s, typically bathed once a week (on Saturday in anticipation of going to church on Sunday). The task of fetching water and heating it was onerous and time-consuming–probably wasteful too, since water was scarce. Bathing in the middle of the week was a big deal, and that phrase would have been the author’s cue to her readers just how giddy everyone was feeling. The phrase was there to express extreme surprise. As in, “Can you believe we took baths in the middle of the week? Wow!!”

Although my daughter is an attentive and intuitive reader, she did not realize this, because that inference, like most inferences, didn’t require “skill.” No amount of reading the Lemony Snickett novels and catching every subtle inference in them (which in fact she had done over the previous weeks) would have made her any more likely to understand how people lived, and when they bathed, on the prairie in the 19th century.

An inference works because something in in the text triggers a connection to knowledge stored in long-term memory. The trigger comes from the connection. So all those people out there telling you that facts don’t matter because you can just look anything up on Google are getting the science of how the brain works backwards. Inferences are generated by knowledge in your long-term memory, not by a decision to seek out–and Google?–a connection.

If I’d asked my daughter what inference she could draw from the phrase “in the middle of the week,” she would have spent a long time guessing and almost certainly would never have made the correct connection. No amount of insight about Laura’s or Ma’s motivations, no yearning to make an inference because I’d asked her to, would have helped her realize that Laura’s family would usually have only bathed on Saturdays. So instead I simply explained to her what it was like on the prairie and that people in that time and place only bathed once a week. We talked a bit about all the labor it would have required to take a bath. Then I asked her, “How would Laura have probably spoken that line?” and she dramatized it perfectly, capturing in her voice just the right tone of surprise and excitement: “in the middle of the week!

In other words, I found it much more beneficial to give her knowledge and ask her to apply it than to have her guess away at an inference that no amount of skill could help her make.

Doug Lemov ( is managing director of the Teach Like a Champion team at Uncommon Schools. He blogs at Follow him on Twitter @Doug_Lemov