In order to know how to teach vocabulary, it’s important to know how vocabulary is learned because it should influence the way that you introduce new words in the classroom. The old way of introducing words was, kind of, to give kids a word list and have them learn the definitions, but that’s not the way words are learned naturally. And so, it’s not the most effective way to teach vocabulary. Vocabulary is learned through a process called fast mapping. Fast mapping is a two-step process. First, the child establishes a referent. So, you look at a referent and in this example, we’ll use a dog. So, the dog is the referent and the child establishes a definition for a dog. So, that first step is establishing the definition; what is the definition of a dog? Well, when you’re two or three, a dog is an animal with two ears, four legs, and a tail. And then, that particular referent becomes the prototype for everything after that. Okay, once the child has the referent and now has this definition of dog, the next step is to refine the definition because we all know as adults that every animal with two ears, four legs, and a tail is not a dog. But in the beginning, for a child, every animal that fits that particular profile is a dog. And so, it’s the child’s job to learn that if that animal that fits those same characteristics moos, it’s not a dog, it’s a cow. If a dog can bark, it’s a dog. If it can’t bark, it’s still a dog. That’s a refining process. So, the child, over time, is learning the difference, in this case between animals, by figuring out which characteristics apply to which animals. And so, the vocabulary process for fast mapping is; I look at the first referent, I map on a definition of what that is, and then I refine it over time.

Now that you know that that’s how a child learns vocabulary, what does that mean for teaching? Well, it means first of all, as a teacher, you have to recognize that the child learns the first definition for that word that he or she hears, maps it on. It becomes the prototype. That’s what fast mapping means. It happens immediately. So, when you’re teaching in the classroom, if you keep that in mind it should influence the way you present new words. One of the tactics that we often see teachers using that we discourage because of the fast mapping process, is the technique where you say, “Does anybody know what a pyramid is?” And all the kids in the class raise their hands and the first three or four definitions are wrong because in that classroom there are fifteen other kids, and among those kids, someone has mapped that wrong definition onto pyramid. So, since we know that fast mapping is the method by which kids initially establish reference, what we would do instead is say, “A pyramid is…” And tell the children what the definition of a pyramid is. Then, in the second class you can say, “Does anybody remember what a pyramid is?” But, by establishing the definition yourself from the beginning, telling children what it is, you ensure that the majority of children, if not all of them have the appropriate definition first. They fast mapped that definition and then they can refine from there. In the absence of a specific definition from the teacher, however, you allow children to come up with definitions that are not accurate. And so, in the second class, instead of talking about your definition again, you are undoing the wrong learning that you established in the first session because kids were picking up the wrong definition from their peers.