This video by the National Council of Teachers of Mathematics (NCTM) explains the importance of conceptual understanding. They explain that many students are taught to just memorize algorithms but when they are faced with a problem where they need to use the math they have learned, they have no idea how to use the algorithm. It is easy to give students specific questions that look similar so they can practice the algorithm and develop procedural fluency, but once an open ended, real-life problem is to be solved they are not able to pick out a solution. The video explains that this is because the students don’t have a conceptual understanding, they are never taught the “why?” behind a mathematical procedure.