What is Skill Development?

Skill development is where the teacher identifies the skill(s) within the lesson objective(s).  The teacher works to provide a step-by-step process, method, or approach for the students to use.  This is where the teacher models the steps while solving real problems.  Lastly, during this time, the teacher provides multiple checks for understanding.
Take a look at this video that shows the development of how to solve the problem, modeling of how to solve the problem, and finally, checking for understanding.