A Model for Understanding Article Reflection

I found this article quite interesting. I think that we, as teachers do in fact need to have a vision of what understanding looks like. This article gives us many ideas of how to check for understanding when teaching mathematics. It was very surprising to me that the article was written thirty years ago, because it is still very relevant today.
I greatly enjoyed all of the example questions that can be asked to check for understanding of concepts, processes, and facts. I think that it is hard to determine whether a student is truly understanding what the material is on a deep level, or if they are simply memorizing what they can and pretending to understand. One example I found to be a good idea was when talking about prime numbers, asking "I have a prime number written on the back of this card; what can you tell me about it?" This is an excellent way to determine if the students truly understand what makes a number prime. The ability to generalize what they have learned and talk about it in their own words will often show that they have a deep understanding.