I defined thinking as combining information in new ways.The information can come from long-term memory—facts you’ve memorized—or from the environment.
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Thinking well requires knowing facts, and that’s true not simply because you need something to think about.The very processes that teachers care about most—critical thinking processes such as reasoning and problem solving—are intimately intertwined with factual knowledge that is stored in long-term memory (not just found in the environment).
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Critical thinking processes are tied to background knowledge. The conclusion from this work in cognitive science is straightforward: we must ensure that students acquire background knowledge parallel with practicing critical thinking skills.
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The phenomenon of tying together separate pieces of information from the environment is called chunking. The advantage is obvious: you can keep more stuff in working memory if it can be chunked.
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So factual knowledge in long-term memory allows chunking, and chunking increases space in working memory.
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A number of studies have shown that people understand what they read much better if they already have some background knowledge about the subject. Part of the reason is chunking.
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Background knowledge allows chunking, which makes more room in working memory, which makes it easier to relate ideas, and therefore to comprehend.
Background knowledge also clarifies details that would otherwise be ambiguous and confusing.
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It’s worth noting that some observers believe that this phenomenon—that knowledge makes you a good reader—is a factor in the fourth-grade slump. If you’re unfamiliar with that term, it refers to the fact that students from underprivileged homes often read at grade level through the third grade, but then suddenly in the fourth grade they fall behind, and with each successive year they fall even farther behind.The interpretation is that reading instruction through third grade focuses mostly on decoding—figuring out how to sound out words using the printed symbols—so that’s what reading tests emphasize. By the time the fourth grade rolls around, most students are good decoders, so reading tests start to emphasize comprehension. As described here, comprehension depends on background knowledge, and that’s where kids from privileged homes have an edge.They come to school with a bigger vocabulary and more knowledge about the world than underprivileged kids. And because knowing things makes it easier to learn new things (as described in the next section), the gap between privileged and underprivileged kids widens.
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Books expose children to more facts and to a broader vocabulary than virtually any other activity, and persuasive data indicate that people who read for pleasure enjoy cognitive benefits throughout their lifetime. I don’t believe it is quite the case that any book is fine “as long as they’re reading.” Naturally, if a child has a history of resisting reading, I’d be happy if she picked up any book at all. But once she is over that hump, I’d start trying to nudge her toward books at the appropriate reading level. It’s rather obvious that a student doesn’t gain much from reading books several grades below her reading level. I’m all for reading for pleasure, but there are fun, fascinating books at every reading level, so why not encourage age-appropriate materials? It’s just as obvious that a too difficult book is a bad idea.The student won’t understand it and will just end up frustrated.The school librarian should be a tremendous resource and ally in helping children learn to love reading, and she is arguably the most important person in any school when it comes to reading.
