I start off by having students write the focus question (How can you use the engineering design process to make a hoopster fly the greatest distance?) in their science notebooks. For this lesson, I have them write as many of the 5 steps in the engineering design process as they can remember to activate their prior knowledge. After they write on their own, I have them share with their tables, then briefly review as a class.
Next I introduce the word constraint. I have them write the word and definition (a limit, such as time, materials, or cost) in their science notebooks. We discuss what constraints they had in for straw rockets (really, it was only time, but it could have been materials as well).
I show them how to make a hoopster, and demonstrate throwing it like a paper airplane. I then tell the class to use the engineering design process to create their own hoopsters under the constraints they may only use paper, straws, tape, and scissors, and you must be finished within 25 minutes.
I have at least two straws per student, and plenty of scrap paper. You could cut the paper into strips ahead of time to save time, but I think letting students cut their own strips makes them more willing to try new ideas when they make their own.
As they work and test, I ask guiding questions such as "What were you thinking you might change about your hoopster?" and "How might that affect the way your hoopster flies?" Questions like these make assumptions that communicate "I know you have a good idea, I can't wait to hear about it and see how it works."
I then have them respond to the following questions in their science notebooks:
This question reinforces both the process that is the focus of the unit, and the vocabulary that is the focus of the day. To support their answers, I ask what they would have done if they didn't have to work within those constraints.