Build a model. Follow the energy. Explain what changes when one connection is removed.
Learning target
I can connect food chains into a food web and use arrows to explain how energy moves between organisms.
01 / NOTICE THE CONNECTIONS · 3 MINUTES
One habitat. Several paths.
A food chain traces one feeding pathway. A food web connects several pathways. Read each arrow as “energy moves to.”
See how the whole web connects.
Each arrow follows energy from a food source to the animal that eats it.
Grass
Grasshopper
Rabbit
Mouse
Frog
Hawk
Read the three energy pathways
Model boundary: these are selected feeding relationships for this activity, not a complete list of each animal’s food sources. Grass and grass seeds represent the same producer.
02 / BUILD THE WEB · 5 MINUTES
Six organisms. One connected model.
Copy these six names onto paper cards. Place each organism once on your page. Use the feeding information to connect the cards with arrows pointing from the food to the eater.
01 / PRODUCER
Grass
Uses sunlight to make its own food. Include its seeds in this card.
02 / CONSUMER
Grasshopper
Eats grass in this model.
03 / CONSUMER
Rabbit
Eats grass in this model.
04 / CONSUMER
Mouse
Eats grass seeds in this model.
05 / CONSUMER
Frog
Eats grasshoppers in this model.
06 / CONSUMER
Hawk
Eats frogs, rabbits, and mice in this model.
Check your model: you should have six organism cards and seven feeding arrows. Add the Sun beside the grass with a different-colored arrow for incoming sunlight. The Sun is an energy source, not an organism.
Decomposers, including fungi and bacteria, break down dead material from throughout a food web. They are important but are not drawn in this six-organism model.
03 / REASON WITH THE MODEL · 4 MINUTES
Make a claim. Show the connection.
Follow one path
Trace energy from grass to hawk along two different routes. Explain why both routes can belong to the same food web.
Change one population
Imagine that fewer grasshoppers are available. Which animal loses a food source shown in the model? Explain one possible effect using the arrows as evidence.
Notice the model’s limits
Can we conclude that every hawk will disappear? Use the other feeding paths to explain why that conclusion is not supported.
Discussion frame
“If ___ decreases, ___ might ___ because the model shows ___.”
04 / CHECK UNDERSTANDING · 3 MINUTES
An exit ticket with evidence.
Respond independently
Name: ____________________ Date: __________
- What does the arrow from grass to rabbit mean?
- Name the producer and explain how it gets energy.
- Identify two food sources available to the hawk in this model. Why does that matter when one population changes?
FOR THE TEACHER
Answers & teaching notes.
Open the model and discussion key
Seven feeding arrows: grass → grasshopper; grass → rabbit; grass seeds → mouse; grasshopper → frog; frog → hawk; rabbit → hawk; mouse → hawk.
- Two paths: accept any two shown above. The same grass and hawk connect the paths; food webs can include multiple routes for energy transfer.
- Fewer grasshoppers: the frog has less of one food source shown here. Frogs might have less food available, which could affect their population. The drawing alone cannot tell us the size of that effect.
- Hawks: the model also shows rabbits and mice as food sources. It does not support a claim that all hawks disappear.
Open the exit-ticket key and reteaching notes
- The rabbit eats grass, transferring energy from the grass to the rabbit.
- Grass is the producer. It uses energy from sunlight to make food.
- Accept any two: frogs, rabbits, mice. Multiple feeding connections mean that the hawk has other food sources represented in the model, though their availability is not guaranteed.
If arrows are reversed: ask “Where does the energy start, and where does it go?” Have students read one arrow aloud before revising.
If answers are absolute: ask students to name what the model shows and what information is missing. Encourage evidence-based predictions using “might” or “could.”
Small-group support: start with grass → rabbit → hawk. Add one branch at a time, then return to the full web.
CONTINUE THE LESSON
Ready for digital practice?
Explore the actual pages in LVL Up! Science: Organisms & Their Environment before choosing the resource.
The free lesson above is complete on this page. The digital resource is a separate purchase.
Planning note: the paid resource includes older TEKS labels. Review its product-page standards note before using it in your current curriculum or STAAR preparation.
Science reference: NOAA · Food webs and energy flow. The classroom example and questions on this page are an original STEAMspirations teaching activity.