The Context of Prior Knowledge

Take a moment and read the following paragraph:

Two experiments investigated visual processing asymmetries in normal and dyslexic readers, with unilateral tachistoscopic presentations. The experiments employed randomized or blocked presentations of verbal and nonverbal materials to determine whether previously reported differences between dyslexics and normals were due to structural hemispheric differences or to strategical processing differences. The results indicate that if dyslexics are unable to predict the nature of the stimulus, they behave as normal readers. Their atypical laterality emerges only when they can adopt a strategy in anticipation of a specific type of stimulus (Underwood & Boot, 1986, p. 219, reprinted from Readence, Moore and Rickelman, 2000).

Great! Now retell it what you just read in your own words without looking at it again. You may have had everything going for you including motivation, ability to decode the words, and perhaps enough prior knowledge to at least recognize the word "dyslexic". Chances are though that you may not have known what processing asymmetries, unilateral tachistoscopic presentations, or randomized or blocked presentations meant unless you already knew what it meant. In other words, your comprehension was compromised because of a lack of knowledge.

As a content teacher, I want to plan accordingly then when examining a text I want my students to read. Now prior to looking at the text I have already established the learning outcomes, written the assessments, know why this particular text will help my students build the knowledge or skills they need to be successful. Having an awareness what the text offers and what my students already know helps me to determine what I need to provide. In other words, I look for the gap between what is known and what is needed to be learned and decide how best to bridge, or scaffold, that gap for my students.

My students will often tell me, "but I don't know anything!" Students know this not to be a true statement as do teachers. We are exposed on a daily basis with a barrage of new information. What we retain long term and how we recover that knowledge is what I'm after. There are enduring understandings I want my students to remember forever. There are also skills and tidbits of knowledge that I need them to hold on to until I can get them to recall them to build new knowledge. So what students are really telling us is, "I don't know how to access what I already know !"

Activating prior knowledge is key to learning new information. Read the following paragraph:

The procedure is actually quite simple. First you arrange items into different groups. Of course one pile may be sufficient depending on how much there is to do. If you have to go somewhere else due to lack of facilities that is the next step; otherwise, you are pretty well set. It is important not to overdo things. That is, it is better to do too few things at once than too many. In the short run this may not seem important but complications can easily arise. A mistake can be expensive as well. At first, the whole procedure will seem complicated. Soon, however, it will become just another fact of life. It is difficult to foresee any end to the necessity for this task in the immediate future, but then, one can never tell. After the procedure is completed one arranges the materials into different groups again. They they can be put into their appropriate places. Eventually they will be used once more and the whole cycle will then have to be repeated. However, that is part of life (Bransford & Johnson, 1972, p. 722, reprinted from Readence, Moore and Rickelman, 2000).

Any idea what this paragraph is about? Doesn't make much sense does it? What if you were to go back and read it again with the knowledge that it is about washing clothes? Imagine how your students feel. Completely capable of reading the words and the sentences but unable to understand because of not activating their prior knowledge.