Lab 11. Food Webs and Ecosystems: Which Member of an Ecosystem Would Affect the Food Web the Most If Removed?

Enderle, Bickel, Gleim, Granger, Grooms, Hester, Murphy, Sampson, and Southerland
Type Category
Instructional Materials
Lesson/Lesson Plan , Activity
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.



This activity in the published book, Argument-Driven Inquiry in Life Science: Lab Investigations for Grades 6-8, is a 4-5 day lesson sequence that requires students to analyze data about the various species found in an ecosystem.  The resource gives thorough teacher background, as well as access (via the NSTA website) to slides that students will use to gather data on each species.  The resource gives some great ideas for discussion with the students in order to reflect on the concepts and investigation-design that the students participate in.  The student pages include some background information as well as a scenario that the guiding question is based on.  Since the students use the slides (provided) to acquire data, there is not much to set up prior to having the students complete the task.  The questions that the students are given allow them to develop an argument and require them to use evidence and justification to support the argument that they make.  This is allows them to learn a format to follow when developing a scientific argument.

For student materials, see three documents for lab 11 that can be accessed on-line at Teacher materials are in the purchased book. 

Intended Audience

Educator and learner
Educational Level
  • Grade 8
  • Grade 7
  • Grade 6
  • Middle School
Access Restrictions

Available for purchase - The right to view, keep, and/or download material upon payment of a one-time fee.

Performance Expectations

MS-LS2-4 Construct an argument supported by empirical evidence that changes to physical or biological components of an ecosystem affect populations.

Clarification Statement: Emphasis is on recognizing patterns in data and making warranted inferences about changes in populations, and on evaluating empirical evidence supporting arguments about changes to ecosystems.

Assessment Boundary: none

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

Comments about Including the Performance Expectation
The prompts that are provided in the student packet work well to scaffold students as they develop an argument and support it with evidence, as well as justify why the evidence counts to support the evidence they cited. Teachers may need to engage students in developing a sample argument as a class through discussion, so students can see that specific details are required within the evidence and justification. In order to include the physical components of an ecosystem, as the Performance Expectation lists, the teacher could use a nonliving part in the example that they model. By modeling the writing development process with the class, the format will be more clear to the students as they work. If students are already able to develop well-supported scientific arguments, the teacher may want to revise the student packet to have fewer prompts.

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
This activity works well to engage students in the technical writing of an argument. The prompts that are provided require the students to include adequate evidence to support their idea and leads them to justify that the evidence is substantial enough to support the argument. If students are already familiar with argument-writing, the teacher could revise the questions to be more open ended and allow the student to develop the ideas with a bit less support.

Disciplinary Core Ideas

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

Comments about Including the Disciplinary Core Idea
The core idea is addressed, almost completely. The only part that is not address, the idea of disruption to physical parts of an ecosystem, could be addressed if the teacher models the writing process by using a nonliving part of the ecosystem, such as drought. It is also important for teachers to check in with student groups as they are developing their arguments to make sure that they are understanding the data that is provided on the slides as well as what the questions are asking.

Crosscutting Concepts

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

Comments about Including the Crosscutting Concept
The arguments that the students develop explain the reason for changes in the ecosystem. The students also need to recognize that the stability of every ecosystem is dependent on the biotic and abiotic factors maintaining their numbers and conditions. The teacher needs to specifically bring this to students’ attention as they develop their ideas. As a scaffolding approach, it would be helpful for students to have a list of terms that are required to be used in their arguments. Terms like stability, change, etc could be included so that students are specifically addressing them in the context of their argument. The resource includes the Crosscutting Concepts of Systems & System Models and Energy & Matter. While both of these Crosscutting Concepts are partially addressed by the resource, Stability & Change is more completely developed.

Resource Quality

  • Alignment to the Dimensions of the NGSS: This resource works well to include the 3 dimensions in a logical and intertwined manner. Students will have to analyze the features of the ecosystem in order to find evidence for their arguments. They will also have to predict the changes that will occur if any species were to be absent from the system. The three dimensions are incorporated in the course of the lesson sequence, but the instructor is ultimately responsible for ensuring that they are not skimmed over.

  • Instructional Supports: The instructional supports are well developed and the questions are thought provoking. Some students may find the questions high level, but all students should eventually be exposed to writing arguments. Teachers can scaffold as needed, but content should be kept intact to be sure the 3 dimensions are explicit to the students.

  • Monitoring Student Progress: The context, including phenomena, questions, or problems, motivates students to engage in three-dimensional learning. Although the student handouts provide a great framework for students to generate ideas, teachers will need to check in with each group regularly to be sure they are on track to develop a strong argument with clear evidence. As the sequence will take several days to complete, teachers could use an exit ticket at the end of each day to check individual understanding.

  • Quality of Technological Interactivity: The entire book is available in paper copy as well as e-book. For both versions, the printables and slides specific to this chapter are housed on the NSTA website, requiring an internet connection and either PowerPoint or a PDF reader.