Life Science · Ecosystem Connections
Ecosystem Modeling: What Happens When One Population Changes?
Build and revise a simple ecosystem model, then use evidence to predict how a change in one population can affect connected organisms.

Lesson plan
Ecosystem Modeling: What Happens When One Population Changes?
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Lesson overview
What students will learn
- Build a model that shows feeding and resource connections among organisms in an ecosystem.
- Use a model and data to predict possible effects of a population increase or decrease.
Key science ideas
- Organisms in an ecosystem are connected by feeding relationships and shared resources.
- In this lesson, a feeding arrow points from the food or matter source to the consumer that receives it, such as grass → rabbit.
- A change in one population can affect organisms connected to it.
Lesson at a glance
- Grade 4
- 50 min
- ~10 min prep
- 5 materials
What’s included
- Lesson Plan
- Investigation
- Teacher Slides
- Printable Worksheet
- Teacher Answer Key
- Interactive Activity
- Vocabulary