Description
What our Nitrogen Cycle STEM lesson plan includes
Lesson Objectives and Overview: Nitrogen Cycle STEM explains the steps in this important life process. Students will learn what happens in each stage. In addition, they will understand why the nitrogen cycle is important to the survival of life on Earth. This lesson is for students in 5th grade and 6th grade.
Classroom Procedure
Every lesson plan provides you with a classroom procedure page that outlines a step-by-step guide to follow. You do not have to follow the guide exactly. The guide helps you organize the lesson and details when to hand out worksheets. It also lists information in the yellow box that you might find useful. You will find the lesson objectives, state standards, and number of class sessions the lesson should take to complete in this area. In addition, it describes the supplies you will need as well as what and how you need to prepare beforehand.
Options for Lesson
In the “Options for Lesson” section of the classroom procedure page, you will see some suggestions for additional activities or ideas to add to the lesson if you want to. Students research how humans impact the nitrogen cycle through fertilizer use, pollution, or deforestation. Students could find and summarize a real news article about nitrogen pollution, farming, or climate change. Students design an imaginary creature that helps with the nitrogen cycle. Create cards with nitrogen cycle vocabulary on one side and simple definitions or pictures on the other.
Teacher Notes
The paragraph on this page provides a little more information or guidance on what to expect from the lesson. You can use the blank lines to record any thoughts or ideas you have as you prepare.
NITROGEN CYCLE STEM LESSON PLAN CONTENT PAGES
What Is the Nitrogen Cycle?
The Nitrogen Cycle STEM lesson includes two content pages. Nitrogen is one of the most essential elements on Earth. It is a gas that makes up about 78% of the air around us. Even though we always breathe in nitrogen, our bodies can’t use nitrogen gas directly. Still, we need nitrogen to live. Our cells need it to build proteins, one of the building blocks for muscles, skin, and even our brains. It is also used to make DNA, the special code that tells cells how to work.
Even though there’s a lot of nitrogen in the air, it’s in a form called N2, which is very stable. This means it doesn’t easily react with other substances. Plants and animals can’t use N2 gas, so it has to be changed into different forms. To solve this problem, nature uses the nitrogen cycle, transforming nitrogen into chemical forms that living things can use.
Steps in the Cycle
The first step in the nitrogen cycle is nitrogen fixation. This is when special bacteria in the soil or in the roots of plants like beans and peas (called legumes) take nitrogen gas from the air and change it into ammonia (NH3). This is a form of nitrogen that plants can start to use. Nitrogen fixation also occurs with lightning. When it strikes, the heat and energy cause nitrogen in the air to combine with oxygen. Then, when it rains, it reaches the ground, making it usable for plants.
After nitrogen becomes ammonia, another group of helpful bacteria in the soil performs a process called nitrification. These bacteria turn ammonia into nitrites (NO2) and nitrates (NO3). Nitrates are the best form of nitrogen for plants. Plants absorb nitrates through their roots, just as they absorb water. Then, they use the nitrogen to make plant cells, leaves, stems, and fruit.
Plants are producers, which means they make their own food using sunlight, water, and nutrients like nitrogen. However, animals cannot make their own food as plants do. Animals (humans included) eat plants containing nitrogen. When a cow eats grass or a rabbit eats lettuce, they get nitrogen from the plants. This nitrogen becomes part of the animal’s body, helping it build strong muscles, blood, and tissues. When humans consume meat, they ingest some amount of nitrogen-containing compounds. Nitrogen is primarily in the form of proteins.
Decomposition and Denitrification
When a plant or animal dies, its body does not disappear immediately. It starts to decompose, which means it is broken down into simpler materials. This job is done by tiny living things called decomposers, such as fungi, worms, and bacteria. These organisms break down dead plants and animals and release ammonia into the soil. This starts the nitrogen cycle over again.
Another group of special bacteria performs denitrification. This means they take the leftover nitrates in the soil and change them back into nitrogen gas (N2), which goes back into the air. This helps keep the balance of nitrogen in the atmosphere. Nitrogen would pile up in the soil without denitrification and not return to the air.
Every step in the nitrogen cycle is a chemical reaction. A chemical reaction is a process where one substance changes into another. For example, when bacteria turn ammonia into nitrates, they create new molecules. Chemical reactions happen constantly in nature, even when we can’t see them!
The Help of Farmers
Farmers often use fertilizer to add extra nitrogen to the soil to help crops grow. But too much nitrogen can be a problem. It can wash into rivers and lakes, causing too much algae to grow. These algae use the oxygen in the water and can hurt fish and other animals. That’s why using nitrogen wisely and protecting our environment is essential.
We can help the nitrogen cycle by planting cover crops, like clover, that naturally add nitrogen to the soil. We can also protect wetlands from bacteria that carry out denitrification. Scientists are working to understand how to keep the nitrogen cycle balanced so that plants, animals, and people all stay healthy.
NITROGEN CYCLE STEM LESSON PLAN WORKSHEETS
The Nitrogen Cycle STEM lesson plan includes three worksheets: an activity worksheet, a practice worksheet, and a homework assignment. Each one will reinforce students’ comprehension of lesson material in different ways and help them demonstrate when they learned. Use the guidelines on the classroom procedure page to determine when to distribute each worksheet to the class.
NITROGEN CYCLE THEATER ACTIVITY WORKSHEET
For this fun activity, students will get to play with the teacher as they act out a fun script. The teacher will read the script as the students do the actions that correlate with each part of the script. Have students read through the script to familiarize themselves with what they’re going to do.
COMIC STRIP PRACTICE WORKSHEET
This fun worksheet will have students create a comic strip that shows the journey of the nitrogen atom as it travels through the nitrogen cycle. Students will follow the guidelines of the worksheet and then write one sentence at the bottom of the page that explains why the nitrogen cycle is essential to life on Earth.
REVIEW HOMEWORK ASSIGNMENT
For the homework assignment, students will label five parts of the nitrogen cycle diagram using the terms in the word bank.
Worksheet Answer Keys
If you choose to administer the lesson pages to your students via PDF, you will need to save a new file that omits these pages. Otherwise, you can simply print out the applicable pages and keep these as reference for yourself when grading assignments.
