The Arizona STEM Acceleration Project

Ponderosa Pine Forests Part 2: Duff Collection Engineering

Ponderosa Pine Forests Part 2: Duff and Collection Engineering

A 6th grade STEM lesson

Lisa Barnard

1/6/23

Notes for teachers

My students worked in groups for this activity to also work on our collaboration skills.

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Depending on how long your classes are and how quickly the students work through the activities, this could take from 2-4 days.

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Depending on how many days your students need to build, test, rebuild, this lesson could go more than one day.

List of Materials

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• Duff samples in tubs from the previous lesson.
• Kitchen scales to weigh the sample in grams. We have scales already at our school, but this is a cheap option on Amazon that weights up to 11 lbs- Scale
• Engineering materials students can use to build something to collect duff with. Some ideas include: straws, string, paper clips, cardboard, paper, index cards, paper plates, foil, twine, crafting wire, etc. I always let students bring in their own supplies too if they get it approved in their design.
• Each student needs a copy of the Duff Recording sheet Duff Engineering Challenge

Standards

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AZ 6th Grade Science:

6.L2U3.11 Use evidence to construct an argument regarding the impact of human activities on the environment and how they positively and negatively affect the competition for energy and resources in ecosystems.

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AZ 6th Grade Math:

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6.SP.B.5: Summarize numerical data sets in relation to their context by:c. Giving quantitative measures of center (median and/or mean) and variability (interquartile range and/or mean absolute deviation), as well as describing any overall pattern and any striking deviations from the overall pattern with reference to the context in which the data were gathered.

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Standards

Science and Engineering Practices

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• ask questions and define problems
• develop and use models
• plan and carry out investigations
• analyze and interpret data
• use mathematical and computational thinking
• construct explanations and design solutions
• engage in argument from evidence
• obtain, evaluate and communicate information

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Objective(s):

I will collaborate and communicate effectively to complete an engineering design challenge.

I will evaluate which design met the goal of the engineering design challenge by analyzing data.

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Agenda (2-4, 50 minute class periods)

Photo Warm-up

Engineering Challenge

Test and Share

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Warm-up Question

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What do you notice is different in these two photos? Which forest would you say is the healthier forest? Why?

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Let’s Review!

Potential Benefits

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• Retains water for the soil
• Regulates soil temperature
• Decomposes to create nutrient-rich soil
• Prevents erosion

Potential Harms

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• Can cause wildfires to spread more quickly
• Too much duff can lead to smoldering and lingering fires which can destroy older pines

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What is duff? It is the layer on the forest floor that is made up of needles, branches, pinecones, pieces of bark, and other organic material.

Engineering Challenge: Let’s Control the Duff!

• You will be working in a group for this engineering activity.
• We will be creating something that can help pick up some of the duff that collects on the forest floor. How can we lessen the chances of a devastating forest fire?
• Your creation should be something that is efficient and easy to use.
• Our goal is to collect the most duff without using your hands in 1 minute.

Materials:

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You must use at least 3 different materials for this project.You will be allowed to choose from the area of materials in the classroom.

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You will be creating an initial design, testing it, and redesigning.

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When you have finished, you will be timed and see how much duff your invention can collect. You can calculate the mass on a scale.

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You will have a recording sheet to keep track of your brainstorm, builds, and redesigns. You will also keep track of data on the final testing round.

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Duff Engineering Challenge

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It’s Data Time!

Let’s look at our averages! How did you calculate the average? I will call on each

group to share their average.

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1. Let’s find the average for our whole class!
2. What do you notice about the data?
3. Are there any outliers? Numbers that are far away from our class average?

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Engineering Challenge Group Presentation

• You will be meeting with your team for 2 minutes to discuss who will be the speaker(s) for your team.

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1. Summarize your engineering process with us.
2. Share with us your average and how it performed during the final test.
3. Be ready to take 1-2 questions from the audience.

Presentations:

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• Eyes on the speaker
• Be ready to ask a thoughtful, respectful question
• Speak loudly and clearly

Assessment

As students work throughout the project, the teacher should be monitoring their work and asking questions. I like to keep a clipboard with the groups and walk around as I check in with them each day. That way I know who I need to check in with.

For an exit ticket, you could have students write down their thoughts on which group’s design best met our engineering goal and why.

You could also have students vote on the best project and give them a rubric to use as groups are presenting. This would be a great way to not only make sure students are paying attention to other groups, but to also make sure that students are evaluating other work.

Here is a sample rubric the teacher can use for this lesson: Engineering Presentation Rubric

Differentiation

• During the engineering process, ask specific questions to groups that are struggling that help them.
• Make it known to students that they may not get to all of the redesigns and that’s okay.
• If students have technology, put the engineering challenge sheet online so they can use accessibility features such as speech-to-text and text-to-speech.

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Remediation

Extension/Enrichment

Students have plenty of room on their recording sheets for redesigns and notes. Make sure students are really understand the engineering process.

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Challenge students to create a second prototype or try to add another material to their work.

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Challenge students to think of how their invention might lessen the impact of devastating forest fires.