Though geometry lends itself to hands-on exploration and activities, the instructor must take care that the discussion and activities help learners’ understanding. The instructor must not only know the content of a lesson, but also the standards that apply to the concept, as well as the common difficulties and misconceptions that might pop up for a given topic. As learners “gather around” a problem and discuss possible solutions and the thinking processes that accompany solutions, understanding and retention can be increased. Sharing among learners can help them and the instructor learn common pitfalls, the thinking processes that lead to them, and ways to avoid them. Learners tend to use methods which suit them best, but sometimes, knowing a different way to look at a problem can help a learner think out of their “box” for subsequent, similar problems.