SWBAT engineer their machines based on their procedure and design plan. They will also test their machine and propose solutions to any problems they encounter.

Following the engineering plan can be challenging for middle school kids. This project walks them through it step-by-step.

5 minutes

**Teacher Tip: ***This lesson involves the students creating official design sketches to construct an initial model of their design. You will need to provide students with the materials they have provided on their materials list in order for them to build. I also provide a little extra of each, in case they have miscalculated the exact amount of each material. This lesson is an excellent way for the students to test their initial designs and begin to notice any errors in their initial designs. When they begin to build, they often notice what ideas are working and what are not and will make changes accordingly, addressing NGSS Standard MS-ETS1-4. *

To start this lesson, students respond to the following prompt on their student notes sheet:

*Based on your design sketch, explain a possible problem with your machine.*

*Something that might go wrong with our machine is...*

This next prompt gives students a chance to think about what might happen with their machine that they will need to fix using their best problem solving skills. I have students spend about three-to-four minutes writing independently on their notes sheet. After about four minutes, I ask the students to share their responses with their small groups. When about five minutes have passed, I ask each group to share one or two of their problems with the class.

After discussing the problems, I ask other groups to propose possible solutions for the other groups' problems in a class discussion format.

For tips and strategies on how to help students identify problems, see Classroom Video: Making Thinking Visible and Classroom Video: Language Assessment

10 minutes

After the students have had a chance to think about possible problems they may encounter and a few ideas for solutions from other students, they now have an opportunity to discuss solutions with their group members. By responding to the following prompt on their notes sheet, they will have a small group discussion:

*From the problem/s you listed in the ENGAGE, suggest a possible solution for fixing that problem.*

*Something we can do to fix the problem is…*

As students are discussing/writing possible solutions, I am moving around from table to table engaging in their conversation and prompting them to take their solution one step further, or to be more specific in their solution...i.e.* "what do you mean by 'add more tape?' How much more tape will you need? Where will you put it?"*

To see ways in which this directive can become clearer for students, watch Classroom Video: Multiple Modes for a direction-giving strategy.

5 minutes

For a quick independent reflection, I now ask students to respond to the following question individually in their notes:

*Why do you think it’s important to test and make revisions to your machine?*

I want students to understand the importance of the revision during the engineering and design process. Sometimes a quick-write activity like this one is all I need to get students thinking and reflecting on the process. Students start to understand why this is important in this lesson, as referenced in this sample student response.

20 minutes

Now, I give students the chance to implement and test their revisions through building, testing and revising. Students build their machines with the suggested revisions and test their machines three times, recording data for each test, making revisions along the way. The following prompt on the notes sheet guides them:

*Make the revisions to your machine. Test your machine three times, fixing any problems that may arise. Record the results in the chart below. *

*Round 1:*

*Did machine pop balloon? *

*If not, what happened?*

*How can you fix it?*

Round 2:

*Did machine pop balloon? *

*If not, what happened?*

*How can you fix it?*

*Round 3:*

*Did machine pop balloon? *

*If not, what happened?*

*How can you fix it?*

5 minutes

After the revisions and final testing have been performed, students now reflect on the process by individually responding to the following prompt on the notes sheet:

*Did you have to make any changes to your machine?*

*If yes, describe the changes.*

*If your group was successful in all 3 trials, explain why you think your machine was successful. *

Next Lesson