CarbonTIME Decomposers Unit

Contributor
Kirsten Edwards1, Hannah K. Miller2, Christa Haverly1, Christie Morrison Thomas1, Nick Verbanic1, Charles W. “Andy” Anderson1; 1Department of Teacher Education, Michigan State University, 2Education Department, Johnson State College
Type Category
Assessment Materials Instructional Materials
Types
Unit
Note
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be "fully aligned," the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.

Reviews

Description

Decomposers is one of six units in the Carbon: Transformations in Matter and Energy (Carbon TIME) curriculum, which was developed through an NSF-funded research collaboration focused on learning progressions to support environmental literacy.  These units were developed for middle and high school students. The units are designed in three groups; each group increases in scale from the previous one. Students should first complete the foundational unit, Systems & Scale (http://carbontime.bscs.org/systems-and-scale), which uses the process of combustion to build basic concepts of matter, energy, and organic compounds at the atomic-molecular scale.The Decomposers unit is one of three units at the organism level, and students are intended to complete one or more of these three units.  These units are intended to be followed by one or both units at the systems level.  Each organism scale unit focuses on three questions: (1) Where are molecules moving? (2) How are atoms in molecules being rearranged into different molecules? and (3) What is happening to energy?  In the Decomposers unit, students investigate fungal growth and decay through the anchoring phenomenon of molding bread.  The highly guided sequence of six lessons in the unit guides students to identify patterns from their observations, develop a model for fungal growth and activity, and then apply that model to explain the growth of bread mold and other decomposers.  This model includes extracellular digestion, biosynthesis, and cellular respiration.  Extensive supporting infomation is provided within each lesson and on the resources page (http://carbontime.bscs.org/resources). The assessment site (http://ibis.colostate.edu/MSP/CTIME/Index.php) includes pre-/post-tests for each unit and for the overall curriculum.  The overview provided here (http://media.bscs.org/carbontime/files/unit_synopses.pdf) provides a helpful orientation to this complex resource.

Intended Audience

Educator
Educational Level
  • High School
Language
English
Access Restrictions

Free access with user action - The right to view and/or download material without financial barriers but users are required to register or experience some other low-barrier to use.

Performance Expectations

HS-LS2-3 Construct and revise an explanation based on evidence for the cycling of matter and flow of energy in aerobic and anaerobic conditions.

Clarification Statement: Emphasis is on conceptual understanding of the role of aerobic and anaerobic respiration in different environments.

Assessment Boundary: Assessment does not include the specific chemical processes of either aerobic or anaerobic respiration.

This resource was not designed to build towards this performance expectation, but can be used to build towards it using the suggestions provided below.

Comments about Including the Performance Expectation
The authors did not cite this performance expectation, but it is addressed in the optional activity 6.1, “Decomposers without Oxygen.” This activity asks students to read an article about fermentation, use molecular models to represent the process, and answer questions based on the reading and model. Teachers may want to provide students with additional learning experiences on this performance expectation, but this activity could provide an effective transition into those additional experiences.

HS-LS1-7 Use a model to illustrate that cellular respiration is a chemical process whereby the bonds of food molecules and oxygen molecules are broken and the bonds in new compounds are formed resulting in a net transfer of energy.

Clarification Statement: Emphasis is on the conceptual understanding of the inputs and outputs of the process of cellular respiration

Assessment Boundary: Assessment should not include identification of the steps or specific processes involved in cellular respiration.

This resource is explicitly designed to build towards this performance expectation.

Comments about Including the Performance Expectation
Following the introduction and investigation of bread molding in lessons 1 through 3, cellular respiration is directly addressed in lesson 4 of the Decomposers unit. Students use physical molecular models and the overall chemical equation to represent the transformation of matter and energy during cellular respiration. In lesson 6, students use what they have learned to explain the role of cellular respiration in the growth and functioning of bread mold and other decomposers.

HS-LS1-6 Construct and revise an explanation based on evidence for how carbon, hydrogen, and oxygen from sugar molecules may combine with other elements to form amino acids and/or other large carbon-based molecules.

Clarification Statement: Emphasis is on using evidence from models and simulations to support explanations.

Assessment Boundary: Assessment does not include the details of the specific chemical reactions or identification of macromolecules.

This resource is explicitly designed to build towards this performance expectation.

Comments about Including the Performance Expectation
Following the introduction and investigation of bread molding in lessons 1 through 3, extracellular digestion and biosynthesis are directly addressed in lesson 5 of the Decomposers unit. Students use an explanation tool (http://media.bscs.org/carbontime/decomposers/worksheets_assessments/5.3_Explanations_Tool_for_Fungi_Biosynthesis.pdf) to explain the role of biosynthesis in the growth of a mushroom. Students use physical molecular models, with added twist ties, to represent the transformation of matter and energy during digestion and biosynthesis. In lesson 6, students use what they have learned to explain the role of biosynthesis in the growth of bread mold and other decomposers.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
During lesson 3, students engage in an argumentation protocol to interpret the class results from the bread mold investigation. Teachers can use the Evidence-Based Arguments Tool (http://media.bscs.org/carbontime/decomposers/worksheets_assessments/3.3_Evidence-Based_Arguments_Tool_for_Bread_Molding.pdf) and supporting protocol to guide students as they develop and refine arguments as individuals, pairs, and whole class. Argumentation is also supported by the discourse routine, which calls for students to generate multiple possible claims before converging on a consensus claim based on evidence and scientific principles.

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
Students use various models throughout the unit to predict and illustrate the flow of matter and energy between systems within bread mold, mushrooms, and other decomposers. Because students will be using teacher-provided models, rather than developing their own, teachers will need to take special care to ensure that students are developing a meaningful understanding of these models, ranging from chemical equations to conceptual models of metabolic processes. The discourse routine, talk and writing goals, and assessment tips throughout the unit can all help teachers monitor students’ understanding of the models they are using.

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
Overall, students work to develop an explanation for what is happening as mold grows on moist bread. To help them develop the concepts needed for the final explanation, students are guided to develop highly scaffolded explanations of cellular respiration, extracellular digestion, and biosynthesis in mushrooms. In the final lesson of the unit, students move from the specific explanation of the molding bread to a general explanation of fungal growth and function. Student explanations are based on results of the bread mold investigation, models and explanations used throughout the unit, and information provided through teacher presentations. The discourse routine embedded within the unit provides regular opportunities for students to receive feedback from other students and the teacher as they develop their explanations. Explanations are grounded in the laws of conservation of matter and energy.

Disciplinary Core Ideas

This resource appears to be designed to build towards this disciplinary core idea, though the resource developer has not explicitly stated so.

Comments about Including the Disciplinary Core Idea
The role of cellular respiration in providing energy for life processes is highlighted throughout the unit, but especially in lessons 4 and 6. Photosynthesis is not addressed. Fermentation is introduced in the optional activity 6.1, “Decomposers without Oxygen.”

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
In lesson 4, students use molecular models to represent the transformations of matter and energy during cellular respiration in fungi. Students then incorporate these concepts into an explanation of respiration in bread mold and other decomposers. It will be very important for teachers to use the embedded formative assessments and discourse routine to monitor and support student learning as they develop these complex and abstract ideas.

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
Lesson 5 focuses on extracellular digestion and biosynthesis and allows students to develop understanding of this disciplinary core idea. In this lesson, students trace the chemical changes that occur as large organic molecules are broken down and small organic molecules are then used in growth processes. Students use a model with coins to represent breakdown and synthesis, followed by molecular models, to develop their understanding. Students then incorporate these models and information provided by the teacher into an explanation of how mushrooms grow. It will be very important for teachers to monitor and support student learning as they develop these complex and abstract ideas.

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
Students develop and use this core idea throughout the Decomposers unit and finally apply it to explain growth and metabolism in bread mold and other decomposers. The idea is reinforced as students regularly refer back to the three guiding questions about matter movement, matter change, and energy change.

Crosscutting Concepts

This resource is explicitly designed to build towards this crosscutting concept.

Comments about Including the Crosscutting Concept
The “Zooming into Plants, Animals, and Decomposers” activity in Lesson 2 builds on the Powers of Ten Tool presented in the Systems and Scale unit to set a foundation for students’ thinking on the macroscopic, microscopic, and atomic-molecular scales. Throughout the rest of the unit, students work across these levels to model and explain how metabolic reactions at the atomic-molecular scale are connected to processes at the cellular and organismal levels. Most lessons in the unit include explicit prompts, such as connecting questions or graphic organizers, that guide students to think across different scales. Even when these prompts are not provided, teachers can use targeted questioning to guide students’ thinking. Scale is also incorporated into the three questions that guide this unit.

This resource is explicitly designed to build towards this crosscutting concept.

Comments about Including the Crosscutting Concept
Again, the three guiding questions and supporting resources focus students’ thinking on this detail of the energy and matter crosscutting concept. In particular, the rule that “Energy can be transformed, but not created or destroyed” makes this detail explicit throughout the unit. Students’ ability to recite this axiom, though, does not always translate into an ability to apply this concept productively. Thus, the authors suggest that teachers use targeted questions (e.g., What forms of energy are involved? What transformations occur? Does your claim match the rules for the energy question? Why or why not? How is your claim based on the evidence you collected?) to monitor students’ understanding of and ability to apply this crosscutting concept.

This resource is explicitly designed to build towards this crosscutting concept.

Comments about Including the Crosscutting Concept
The Decomposers unit, like each of the Carbon TIME organism level units, focuses students’ thinking on three questions as they work to explain the phenomenon of bread molding: (1) Where are molecules moving? (2) How are atoms in molecules being rearranged into different molecules? and (3) What is happening to energy? These three questions are accompanied by supporting questions, rules to follow, and evidence that can be observed (http://media.bscs.org/carbontime/decomposers/posters_spreadsheets/Three_Questions_11_x_17_Poster.pdf). Together, these guiding questions focus students on analyzing the flows of matter and energy between systems. Students are prompted throughout the unit to revisit these questions, and the questions ultimately provide a framework for students’ final explanations.

Resource Quality

  • Alignment to the Dimensions of the NGSS: The Carbon TIME units are explicitly designed for the NGSS, and the authors provide a unit-level map linking all units to specific performance expectations (http://media.bscs.org/carbontime/files/ngss_mapping.pdf). Teachers can check the NGSS alignment of specific lessons by clicking on the lesson title within a particular unit. Each unit follows a well-developed, research-based instructional model (http://media.bscs.org/carbontime/files/Carbon_TIME_Instructional_Model_8.11.16.pdf) that leads students to investigate, model, and explain phenomena related to the transformation of matter and energy in various carbon-transforming processes. Students engage in nearly all the science and engineering practices, and they repeatedly apply the crosscutting concepts of energy and matter and scale, proportion, and quantity. The Decomposers unit focuses on the anchoring phenomenon of mold growing on bread, and the unit brings in other supporting phenomena to help students develop and use specific elements of the three dimensions. Some content is delivered through direct instruction supported by discussion, but this information is provided within the context of students developing explanations for phenomena. Teachers should use the discourse routine to facilitate interactive discussion in these situations. The instructional model mentioned above provides coherence within the unit, and the full collection of Carbon TIME units were developed in a coherent fashion, as described in the FAQ file (http://media.bscs.org/carbontime/files/Which_Units_Should_I_Teach_FAQ_1.19.16.pdf).

  • Instructional Supports: The anchoring phenomenon is made authentic through a first-hand student investigation. Carbon TIME units are built around a discourse routine (http://media.bscs.org/carbontime/files/Carbon_TIME_Discourse_Routine.pdf) that allows students to express and refine their ideas based on evidence and feedback. Each lesson includes specific talk and writing goals for students, with teacher talk strategies to support these goals. The accuracy and appropriateness of information in this unit is supported by the fact that the Carbon TIME units are based on learning progression research. Information about the learning progression (http://media.bscs.org/carbontime/files/abt201577402_Feature_Article_Parker_.pdf) and grade-appropriate content simplifications (http://media.bscs.org/carbontime/files/Carbon_TIME_Simplifications.pdf) are provided in supporting materials. Each unit includes three instructional pathways that call for explanations and performances below, on, or above grade level for high school students (http://media.bscs.org/carbontime/files/Turtles_07.05.16-1.pdf). Lessons also include suggestions for extending students’ learning. Students’ thinking is highly scaffolded early in each unit, and then this scaffolding is gradually removed as the unit concludes and students construct their own explanations.

  • Monitoring Student Progress: Process tools used throughout the units, such as the predictions tool for bread molding (http://media.bscs.org/carbontime/decomposers/worksheets_assessments/3.1_Predictions_Tool_for_Bread_Molding.pdf), scaffold students’ thinking and provide direct evidence of three dimensional learning. Keys for these tools and assessment guidance are provided for each lesson, allowing the teacher to use these as embedded formative assessments to guide student learning. Assessment items were developed to be accessible to all levels of students, and the pre/post assessments were validated with a sample of students that was diverse in terms of geography, grade level, and academic level (http://media.bscs.org/carbontime/files/CarbonTIMEAssessmentValidation.pdf). However, potential cultural bias of assessments is not addressed in supporting materials. All pre/post tests include assessment guidelines.

  • Quality of Technological Interactivity: The unit is not technology based, but the pre-/post- unit assessments can be administered online. Probeware with carbon dioxide sensors could also be used along with, or in place of, bromothymol blue to detect carbon dioxide production.