Hands-on Activity Aerogel Cookies

Learning Objectives

After this activity, students should be able to:

• Understand properties and uses and potential of aerogels.
• Apply the engineering design process to the design.
• Communicate brainstormed ideas and perform clear research.

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

NGSS: Next Generation Science Standards - Science

International Technology and Engineering Educators Association - Technology

State Standards

Materials List

Teacher Supply List:

• Teacher PowerPoint Presentation
• computer and projector

Each person needs:

• Aerogel Pre/Post-Quiz
• Engineering Design Notebook

Each group needs:

• chocolate chip cookie dough samples, ideally 2-4 per group.
• basic household and/or various chemicals from a school chemical storeroom depending upon group design
• basic household and/or various tools from a school science storage depending upon group design
• safety goggles
• access to the internet and PowerPoint, Google slides, etc.

To share with the entire class:

• aerogel sample from http://www.buyaerogel.com/ or http://aerogeles.com/; alternatively, contact the manufacturer and ask them to donate samples to your class; or, contact the Akron Global Polymer Academy to see if research labs have extra samples available
• packs of sticky notes—two different colors
• index cards
• access to a heating source, such as a Bunsen burner or hot plate
• camera

Worksheets and Attachments

Pre-Req Knowledge

Students should know what a solution is.

Introduction/Motivation

Have you ever mixed oil and vinegar together in a bottle? If you were to pour both liquids in a jar and let them rest for a while, you’d see that the oil would float on top of the vinegar. If you were to put a lid on the jar and vigorously shake it, the oil and vinegar would mix creating something called an emulsion. An emulsion is a heterogeneous mixture of two or more immiscible substances dispersed in each other. Immiscible substances are unable to form a homogenous mixture. If engineers want to create a heterogeneous substance from immiscible substances, they might use an emulsifying agent to prevent the layers from separating back.

An interesting component of research involving emulsion uses a novel substance called an aerogel. Due to their unique structure, aerogels have many properties that make them very useful. One such project of interest to engineers uses aerogels to create coatings for clothing or masks that can filter out contaminants and thus improve our health.

This research involves the design of an aerogel that uses a gel polymer emulsion. This involves soaking the sample in a solution for 24 hours. It is then put into a different solution for another 24 hours, and then a third solution for yet another 24 hours. Finally, the sample is soaked and dried with a supercritical carbon dioxide fluid. The result is an aerogel: a substance with lots and lots of pores that is exceptionally strong and light.

However, aerogels are not widely used because it is still expensive to make them. In this activity, we’ll examine a design process that is used to create these pores, using a model that is familiar to everyone: cookie dough!

Procedure

Before the Activity

A week prior to starting the activity:

• Order aerogel samples from http://www.buyaerogel.com/ or http://aerogeles.com/ or inquire about samples from The University of Akron Global Polymer Academy (https://www.uakron.edu/polymer/agpa-k12outreach/)
• Take some time to explain to students the nature of the design challenge. In this activity, students will mimic the design of an aerogel by using a very unique (and tasty) stand-in: cookie dough. They will design a means for removing the chocolate chips from cookie dough while leaving the holes intact.
• Ask students to consider the following: “You won’t be allowed to remove the chips manually. Instead, you will have to use another substance such as a manmade chemical, or even heat, cold, or pressure. You will also have a voice in some of the design constraints, such as what substances you are allowed to use, cost considerations, etc.
• Watch all videos on the Aerogel Video List. The purpose of this is to give students perspective when they see dry ice or liquid nitrogen in the videos during the project.  There are lots of videos on the internet that you can use for ideas. See below for an example:
• Liquid Nitrogen:     
• Science Experiment LIQUID NITROGEN vs PEPSI - https://www.youtube.com/watch?v=0kMqRhJ_A0c
• Liquid Nitrogen Show! - https://www.youtube.com/watch?v=enEtTV-FyCU
• Dry Ice:
• 5 Phenomenal Science Stunts, Done with Dry Ice - https://www.youtube.com/watch?v=dXq0ao2GmrQ
• 7 Dry Ice Experiments - https://www.youtube.com/watch?v=72fYfqZCwaY
• Make copies of the Aerogel Pre/Post-Quiz and the Engineering Design Notebook.
• Make copies of the Engineering Design Notebook.

With the Students

Day 1-2:

1. Introduce the activity by selecting a volunteer. Have the volunteer face the teacher with both palms up and ask them to close their eyes or use a blindfold. Place an index card in each of their palms, and then place an aerogel sample on one of the index cards. Have the student guess which hand is holding the aerogel. (You can do this with a few volunteers. Alternatively, you can let the students do this to each other.) After this exercise, pass the aerogel around for students to observe.
2. Handout and then collect the Aerogel Pre/Post-Quiz. 

Day 3:

1. Explain to students the nature of polymers, which are a group of compounds with repeating units in a molecular structure. Polymers include plastics, rubber, glue, and other synthetic materials.
2. After handing out the Engineering Design Notebook, explain to the class that they will watch one or two videos from the Aerogel Video List until finished. The class will have time to record answers about the videos in the “Basic Info Section” of their Engineering Design Notebook.
3. Introduce/review problem and engineering design challenge by reading the paragraphs from the Introduction/Motivation section. (These paragraphs are also in their Engineering Design Notebook.)
4. Have a volunteer serve as the class recorder for this next section. The goal is to identify two design constraints for this activity. (Note: the students may note vote to remove the chips manually, and the cookie dough must be in its original shape throughout the activity. Ask the class: “Are there any other design constraints (or rules) that we should consider, such as cost or materials, or even the amount of materials used?”  Have the class vote and then instruct the students record their “Design Constraints” in the appropriate section of the Engineering Design Notebook.
5. Have students complete the first box of the “Imagine/Brainstorm” section of the Engineering Design Notebook. It’s a good idea to assign students into groups at this time.
6. Have students complete the Project Planning Log in the Engineering Design Notebook.

Day 4-6:

1. From Day 4 until the end of the activity:

• Reinforce concepts from the Teacher PowerPoint Presentation, such Habits of Mind, and Engineering Design Process, and Soft Skills.
• Have students watch 1-2 videos from the Aerogel Video List and answer questions in the “Basic Info Section” of the Engineering Design Notebook.

2. Have students work on their challenge by referring to the “Lab Notes” in Engineering Design Notebook and taking pictures as they go. Remind them to be as detailed as possible.

Day 7-8:

1. Turn to the “Mini Presentation Rubric” in the Engineering Design Notebook. Go through it with them in detail. Have students put together a 4-8 slide presentation (less than 7 minutes long) based on their findings.
2. Have students complete the Reflection portion of the Project Planning Log in the Engineering Design Notebook.

Day 9-10:

1. Handout 3-4 rubrics to each team and have them complete the top portion. Then, collect the rubrics and hand them out to audience members before each team presents so the audience can also grade.
2. Hand out two different colored sticky notes to each table. Tell students that when they are not grading, they will write team names along with ‘one great thing about this project is . . .’ and ‘one thing to consider or one way to improve. . .’ on the other before putting the sticky notes in a specific area of the room after each presentation. Have a volunteer check off each student as they turn in their comments to ensure all participate.
3. Have each group present. Have 3-4 students grade. Choose different students each time to grade. Remember to give students time to finish grading and writing on the sticky notes after each presentation.
4. Before class ends, give students time to put their sticky notes on the “Peer Feedback” page of the Engineering Design Notebook and to evaluate comments.

Day 11: 

1. Allow class to evaluate their comments.
2. Have the class decide on “Redesign Constraints” and record them in notebook.  Note: The new constraints are only for the groups that accomplished the challenge in the first round. Those that didn’t accomplish the goal should still work under the original constraints.
3. Allow students to brainstorm again, complete “Brainstorm” page and “Project Planning Log” of the Engineering Design Notebook.

Day 12:

1. Redesign/Retest. Have students record their “Redesign Lab Notes” in their Engineering Design Notebook and take pictures as they go.

Day 13-15:

1. Have students prepare for their final presentation, which includes finishing Reflection portion of Project Planning Log. 

Day 15-16:

1. Final Presentations, using the same peer grading as student used in Day 9-10. Have students do the Self, Group, Peer Evaluation in the Engineering Design Notebook. Finish with the Aerogel Pre/Post-Quiz.

Vocabulary/Definitions

aerogel: An incredibly lightweight solid that made from a gel and is 95-99% air. Because of their strong properties, aerogels are used in a variety of ways, including aerospace engineering research and in the medical field.

compressive strength: The ability of a material to withstand a load.

emulsifying agent: A specific substance that helps a mixture hold together rather than separating into two layers.

emulsion: A heterogeneous mixture of two substances that are dispersed in each other.

heterogeneous mixture: A mixture that does not have a uniform composition.

immiscible: The inability of two substances to dissolve into one heterogeneous mixture.

Assessment

Pre-Activity Assessment:

Pre-Quiz: Conduct the Aerogel Pre/Post-Quiz to gauge student understanding.

Activity Embedded Assessment

Mini Presentation: Complete the various pages of the Engineering Design Notebook and conduct mini presentation.

Post-Activity Assessment

Final Presentation: Students do the final presentation and perform peer evaluation.

Post-Quiz: Have students re-take the Aerogel Pre/Post-Quiz to assess their learning.

Copyright

Contributors

Supporting Program

Acknowledgements

This curriculum was based upon work at the University of Akron supported by the National Science Foundation under RET grant no. EFC-1542358. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.