Our last unit ended with a bang! Unit 5 Pythagorean Theorem and Volume was opened with act 1 of Dan Meyer’s Taco Cart. As with most 3 act tasks, this one began with the notice and wonder component. Students’ ideas exceeded what I expected.
The blue notes the notices, the orange notes the wonders and the black were thoughts added during our discussion about estimations.
We decided to answer “Who got to the Taco Cart faster?” but said we would come back to answer: are they going at the same speed, was one person running and will they get there at the same time? The conversation around the estimation became intense.
To prove our theories we used anglegs and color tiles to mimick the right triangle created by the path Ben and Dan walked to determine the length of the legs using the length of squares. Even as we were building a student kept repeating, “there has to be a part 2 to this, there just has to be”. As students concluded the area of the legs combined or the path Dan walked was the same as the area of the square on the hypotenuse or Ben’s route, the excitement grew even more.
Many thought their estimation of the guys getting to the cart at the same time was correct after the hands on activity. Others held on to the fact that time would play a key role in who got there faster. So I revealed the information for part 2. I love that many students had already developed a rate for the sidewalk to sand speed. Those who shared their conjectures believed the rate was 2 to 1. From the provided information it was determined it was 2.5 to 1.
“I know you are not about to do this to us.”
Then I decided to press the pause button on the task. After students recorded the speed and distances provided on their recording sheet, I instructed them to put the papers in their porfolios to which a student exclaimed, “I know you are not about to do this to us!” Can you say completely hooked?!
We finished the day completing a practice task from Hands-on Standards:
The next day, students came in asking, “Are we doing Taco Cart today?!” Each time I told them, “No, but I promise we will finish it this week.” The suspense grew and grew. Everyday they came in asking the same question. We worked through a few more concept development tasks from the GA Math Frameworks before returning to Taco Cart on Friday.
Students had an opportunity to use everything they learned during the week along with the information obtained in part 2 to work out the problem and develop a conclusion. Some students remained stuck in estimation mode (which was disappointing)
Others focused on using their understanding of the Pythagorean Theorem to form their conclusion but did not factor the time element:
While others were able to make the connections:
This was the best part:
After the screaming subsided, a young lady shouted, “that was intense. We should do this more often!”