Does Knowledge Affect Learning?

A computer with an extremely fast processor is certainly powerful. But without memory or data to work with, such computer is not really that useful. In education, skills are one part, but there is also content. Standing in front of a classroom, a teacher may try to bring the lesson closer to what the students have already experienced. A good teacher often tries to bring the topic to a much more familiar territory. Learning can come easier if not everything is new. Lessons learned inside a classroom are usually not entirely from scratch. Formal basic education in a classroom does not begin in day one, the day a child is born. It starts years after. And every year inside a school builds on previous years. A child's knowledge affects how that child learns.

Esther Quintero of Shanker Blog recently wrote an article describing the research work of Tanya Kaefer (Lakehead University) Susan B. Neuman (New York University) and Ashley M. Pinkham (University of Michigan), "Pre-existing Background Knowledge Influences Socioeconomic Differences in Preschoolers’ Word Learning and Comprehension". The work addresses the following questions:
  1. Do poor and middle class children possess different knowledge about the world?
  2. Do differences in knowledge influence the children’s ability to learn in the classroom?
  3. If differences in preexisting knowledge were neutralized, would the two groups of children learn similarly?
To answer these questions, specific lessons on birds are used. The answer to the first question is shown in the following table. These are results from tests that involve dichotomous questions. Thus, someone without any knowledge about birds should score 50%, assuming all the answers are random guesses.

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Middle income children do show greater background knowledge regarding the topic of birds. For comparison, results from a Peabody Picture Vocabulary Test-III (PPVT) specific on birds are also reported indicating that poor children are indeed weaker in receptive vocabulary in this particular domain of birds.

The second question is addressed by designing a lesson that does require background knowledge. This lesson is described as follows:
For this study, we created an 18-page illustrated storybook about four birds that lived in a house together. The book had a total of 238 words, and shared a common plot and story grammar, including the setting (i.e., house), problem, response, and resolution. The story featured the adventures of four types of birds (all extinct): the moa, faroe, cupido, and kona.
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These are species that are obviously not familiar to young children but the passages and pictures contain items that can be related to general characteristics of birds. Tests on vocabulary as well as reading comprehension in these lessons also reveal that poor children do not perform as well as those from middle-class families:

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The last question is perhaps most interesting. What if the learning is from scratch? In this study, it is important not to make any reference to anything children may have encountered or experienced before. Thus, the lessons are slightly different (no reference to birds):

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And the results highlight the fact that although vocabulary (words in context, since there are really no lessons out there that are in a vacuum) is still different between the two groups, the poor children perform at the same level as rich children in reading comprehension tests:

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Knowledge does affect learning and children as they march through year after year inside a school are building their knowledge, not just skills. The gap created by the difference between the experiences and background knowledge of children from various income groups needs to be taken into account. Otherwise, schools really just become another place where scores depend on a child's socio-economic status.