Learning Querki introduces Things and Models too abruptly

Summary: From Abby: It dives right into Things and Models and Instances, without a lot of explanation. I speak enough programming to guess at why you're assuming that's readily comprehensible, but I think they all require more explanation and examples, along the lines of "The Thing is the top layer, and here are several examples of Things, and then the Model is the next layer and here are several examples of models..." with each of those getting a page's worth of detailed explanation.

This makes sense -- these concepts are crucial, and are worth spelling out a lot of examples to get them across.

She also points out that Properties are never properly explained. This seems to be simply an oversight on my part, and a major one.