In your BPS Standard documents, you will find a very important table referred to as Table 1-Common Addition and Subtraction Situations. Knowing the expectations relating to this table and understanding the various problem types is essential for teachers. By knowing more about the various problem types, we can be certain that we are providing our students with not just one or two types of problem situations, but several.
In a K-1 training that was done by Nancy Low of Math Solutions, participants started the day by writing an addition "word problem" and a subtraction "word problem". Then they engaged in learning more about the various problem types for addition and subtraction. Participants were given word problems and had to categorize these into specific groups.
At the end of the session, participants were asked to look back at the 2 problems they wrote. They then put a sticky note under the problem types that their problems fit under. (Example: If your problem was a Join with Result Unknown problem, you then put a sticky note in that section.) What we discovered is that we tend to provide students with the same types of problems. This was a great ah-hah for all of us!