# Cartober: Challenge 3: How many 50g blocks do you have, Ms. Tice????

Our final challenge for Cartober took the remaining Fridays in the month of October.  The first step was making a car that would have a place to carry up to ten 50 gram Lego blocks.  We raced the cars down our ramp in a hallway where the cars could roll as far as possible.  We used rulers to measure the distance each car rolled.

Kids worked in groups of 3 to build their cars.  Once we were ready to start racing them down the ramp and measuring the distance, the kids picked “jobs”.  One kid needed to be the Measurer, one needed to be the Recorder, and one needed to be the Racer.  They would switch jobs with each trial, so that each kid had a chance to measure, record, and race.

The first trial was just the car by itself with no 50 gram blocks.  Each group raced, measured, and recorded.  If a car broke on the way down, the group was allowed to go fix the car.  On the second trial, we added one 50g block.  On the third trial, we added five 50g blocks, and on the fourth trial we added ten 50g blocks.

The building of the car and doing the four trials were not done on the same day.  We split it up so that the kids built a car and raced it with no 50g blocks to get their initial measurement on the first day.  Then we placed the cars in gallon-size ziploc bags and I wrote each group’s names on the bag.  The next Friday, we finished the trials.

After all the trials, we reflected on the effect of the added weight to the cars’ distance.  We talked about what this could mean.  Many kids said they were surprised that the weight would make the cars go so much faster.  They had predicted that the weight would slow the cars down.  Several kids remembered a field trip they took to a local ski resort in second grade to go snowtubing.  They made the connection that it made sense that more weight would make something go faster because when you snowtube, you go farther if you connect more tubes together.

The kids loved Cartober and were sad to see the car racing come to an end.  Little do they realize, but this will not be their last car race…. MUAH HA HA HA HA!