Learning What We Learn, Teaching What We Teach

"What is ml?" Unsure. Litre? "How many millilitres is equal to 1 litre?" Unsure again. So I taught the student the conversion from litres to millilitres and the reverse. Some students will be able to master the formula and “prove” to us that they understand, but do they? As teachers, tutors and adults, will you deceive yourselves and move on to the next skill, telling yourself that the student understands the concept? You should test him for his true understanding. “Look at this packet drink? How much liquid is in it?” Silence. “Guess. Come on.” Silence again. “Come on, just guess.” What sort of Math teacher is this man?" the kid was probably wondering. “I don’t how,” the student finally replied. “I know you don’t know, but just guess.” He kid guessed a number, which was wrong, and then I said, “Look at the packet drink and see how much liquid there is in it.” The child picked up the packet drink and turned it this way and that, searching for a number. “100!...