Fifth grade students here have to figure out how to make a 90 degree turn with their Lego NXT robots. The robot cars they built have 2 motors and they typically turn one motor only on to make a 90 degree turn. But they have to figure out, by trial and error, how long to turn the one motor to make a 90 degree turn. One group today found out that .3 seconds was too short and .4 seconds was too long. So we went up to the board to try and answer the question, “What’s 1/2 way between .3 and .4?” When, after some reflection, one students said .35, the other student had trouble, saying “3.5.” If you add zeroes, it is easier to see that .35 is halfway between .30 and .40. This is the type of math problem I really love because it is real, practical and needs a deep understanding to solve. We hit a lot of problems like it with our grade 5 and 6 NXT robotics program. We have them calculate the velocity of their robot in grade 6, which encourages a deeper understanding and appreciation for long division and ratios (rather than just do worksheets).
