Gardens, Plants, And Ecology

Sustainability: Gardens, Plants, and Ecology

Kristie Kay
Sabrina Peterson
Kelli Rusinsky

NOTE: Many images have been removed for copyright infringement.

The topic that we choose to work with is sustainability with a focus on gardens, plants, and ecology. The reason that we choose this topic is because sustainability is important for the future of life on Earth, which should be important to all of Earth’s occupants. Students will be helping our future environment, so it is very important to teach them about sustainability and how to plant their own gardens. Our overall goals are for the children to understand how and why plants create sustainability including photosynthesis, local food sources, and gardening.

Photosynthesis and Respiration

  • Ask children for their ideas and prior knowledge about photosynthesis.
  • Describe the process of photosynthesis and why it is important to our environment.
  • Provide an example of photosynthesis by placing a plant in a glass container full of water in direct sunlight and observing the bubbles of oxygen that are being released from the plants and rising to the surface.
  • Children will learn about the photosynthesis and respiratory cycle.
  • Children will engage in physical activity in order to see that humans require a lot of energy and need the process of photosynthesis in order to respire. Students will learn this through experimentation. (Students will be breathing hard after physical activity.)
  • Children will complete a respiratory and photosynthesis cycle worksheet.
  • Children can color their worksheets if they would like to do so.

Seed Life:

  • Children will learn the cycle of plant life starting from a seed and ending in a vegetable/fruit/flower/plant.
  • Children will observe different seeds and seed sprouts under the microscope in order to compare and contrast between them.
  • The students will play a game in which they match the seed sprouts to the correct vegetables.


  • Children will select 1-3 seeds to plant and take home with them.
  • Children will learn how to care for their plants including water, soil, and sunlight.
  • The different areas in Flagstaff to get fresh fruits and vegetables will be discussed along with how buying locally reduces the impact on the environment from shipping.
  • Children will be able to taste freshly grown produce from Flagstaff.

Photosynthesis and Respiration

Children will be expected to learn the cycle involving photosynthesis and respiration.
Information that children will learn:
The process by which plants make food is called "photosynthesis". The word "photosynthesis" is made up of two words:
1. "photo" = light
2. "synthesis" = putting together
Plants take in carbon dioxide from the air and water from the soil; put them together (in the presence of light energy and chlorophyll) to produce sugar (glucose) and oxygen.

Chlorophyll is the green pigment found in plants. Both chlorophyll and light energy need to be present for photosynthesis to take place, but they are not used up in the process.

Thus, the process of photosynthesis can be represented as follows:

carbon dioxide + water →→→→→ sugar (glucose) + oxygen
light energy

Like all living things, plants need oxygen to release energy from food for their own life processes. In other words, plants need to respire. Respiration takes place all the time- day and night. During respiration, plants take in oxygen and give out carbon dioxide- the gas taken in and the gas given out is the opposite of photosynthesis! In other words, plants give out oxygen during photosynthesis and take in oxygen during respiration. Some of the sugar produced during photosynthesis is used by the plant for its life processes (such as growing and reproducing); the excess is converted mainly to starch and stored in various plant parts which may be used as food and energy by animals and humans. Oxygen produced during photosynthesis replenishes the oxygen that was used up by living things during respiration. This cycle of photosynthesis and respiration maintains the balance of carbon dioxide and oxygen on earth.

Photosynthesis Respiration
Occurs in the presence of light (and chlorophyll in plant cells) Occurs at all times in cells
Requires energy (light) to make sugar (glucose) Releases energy from sugar
Complex substances (sugar) are formed from simpler ones. Complex substances (sugar) are broken down into simpler ones.
Carbon dioxide and water are the raw materials. Carbon dioxide and water are the waste products.
Oxygen is given out. Oxygen is taken in.

Photosynthesis is the most important chemical reaction on Earth. It is responsible for virtually all energy available for life in the biosphere.

Using chlorophyll, plants (and some algae and bacteria) use sunlight energy to enable a reaction which combines carbon dioxide (CO2) and water (H2O) to form sugars which store energy and release oxygen (O2) as a product back into the atmosphere. This is represented as an equation like the following based on a sugar, e.g. glucose.

photo3.jpg photo4.jpg

During the process of photosynthesis, oxygen is produced. We use this oxygen to breathe.

Plants use some of the carbohydrates they make to release energy for various functions, whilst the rest is used to increase their bulk, in a process chemically similar to burning. This reaction returns carbon dioxide (CO2) and water (H2O) to the atmosphere as well as releasing energy and can be represented by an equation like the following based on a sugar e.g. glucose:

photo5.jpg photo6.jpg

Steps to Teach Students about Photosynthesis and Respiration and the Cycle of the two:

Note: All activities must be completed in this specific sequence.
Students will be asked about their ideas about and/or prior knowledge on photosynthesis.

  • What do you think photosynthesis is?
  • Can you explain the process of photosynthesis?
  • What do you think respiration is?
  • Why do you think these two processes are related?
  • Why do you think that these processes are important?

The process of photosynthesis will be explained as well as its importance for life on Earth. Students will be shown pictures in order to help them understand what is being taken into and given out by the plant.

Students will observe photosynthesis taking place by looking at a plant that is placed in a glass container full of water in direct sunlight. Students will observe the bubbles of oxygen that are being released from the plants and rising to the water surface.

Students will learn about respiration. Students will learn that all plants, animals, and humans need to respire and do so using the oxygen (to breathe) and glucose (for energy) that is produced by plants during the process of photosynthesis.
Students will look at pictures and tables which show the cycle of photosynthesis and respiration.

Students will be asked to think about which needs more energy, a plant or an animal? Students will test their ideas by counting the number of breaths that they take while sitting still. Once that piece of data is recorded, students will engage in physical activity for approximately one minute. (Students may be asked to do jumping jacks if space is an issue.) After one minute, students should count the number of breaths that they take. The number of breaths taken after engaging in physical activity will be much more than the number of breaths taken while sitting still. While sitting still, the students acted as plants, requiring little energy. When engaging in physical activity, the students acted as animals, requiring a lot of energy.

Students will relate their experiments to what they are learning. Students will realize that plants use oxygen and glucose, but very little is needed for their life processes. Students will understand that our energy comes from animals that we eat that eat plants as well as from the plants that we eat ourselves.

Students will have a thorough understanding of the photosynthesis and respiratory cycle by the end of the lesson. Students will apply what they have learned by completing the following student worksheet. Students will be asked to add the two products of photosynthesis that are used in respiration to the worksheet. (The correct products are oxygen and glucose, which should be written on the side of the worksheet in which the arrow is coming from the plant and going to the human.) The student will also be asked to add the two products of respiration that are used in photosynthesis to the worksheet. (The correct products are carbon dioxide and water, which should be written on the side of the worksheet in which the arrow is coming from the human and going to the plant.)

Students will be allowed to color their handout and the pictures on them if they would like to.

Students will be encouraged to take their worksheets home with them.

Plants make glucose (sugar) and oxygen during photosynthesis. Human beings and all animals take in oxygen to breathe, break down glucose molecules to use as energy, and exhale water and carbon dioxide. Plants take in this water and carbon dioxide, along with sunlight (energy) and chlorophyll (green pigment found in plants) in order to photosynthesize and continue the cycle.

Seed Life
When students come to the station, they will be asked what they know about the life cycle of plants, which will help in assessing their prior knowledge of the topic. All activities can be clustered and do not necessarily need to occur in a particular order.

Some questions that will be asked are:

  • What are the parts of a plant?
  • What does a plant need to grow?
  • How does a seed know when to begin growing?
  • What is the plant cycle?

Seed Germination

We will then discuss the life cycle of plants:
It begins with a seed. The outer layer of the seed is called the seed coat. This shell protects the seed from outside elements and keeps it intact. There is a food supply inside the seed called endosperm, which keeps the seed alive and healthy while it is waiting for the right time to start the germination process.

Steps of Seed Germination

  1. The seed absorbs water, which causes the seed coat to burst. This causes an activation of enzymes, increase in respiration and duplication of plant cells.
  2. Chemical energy stored as starch is converted to sugar. This gives the plant the energy it needs to push through the seed coat opening.
  3. The growing plant emerges from the seed in the form of the Hypocotyl (the plant’s stem) and Radical (the plant root). It then places roots (Radicle) to help keep the plant in place and absorb minerals and water from the soil.

After germination, the plant forms its first leaves underground, the pushes toward the surface and source of light from the sun. Then the cotyledon protects the leaves during this process. The leaves form above the epicotyl (the top stem). Once the leaves have reached the sunlight, they use it to make energy to help the plant grow through the process of photosynthesis.


We will also discuss the life cycle of the plant, from seed to plant to flower, to fruit, to seed, as seen in the cycle above.

Children will be able to observe bean, tomato and cucumber plants in each of the stages from seed, sprout and plant. Using a microscope, they will be able to see the germination process in detail and make hypotheses about the different types of seed/sprouts. They will also be able to match the seeds, sprouts and plants together by playing a matching game in order to see the entire life cycle of each vegetable.


Children Will

  • Learn about seasonal fruits and vegetables
  • Learn how to plant their own garden
  • Learn how to help their community by planting a garden for someone/place in need
  • What fruits and vegetables grow in your community

Background Knowledge

Ask Students

  • What are your favorite fruits and vegetables?
  • Do you get to eat these year round?
  • How many have ever planted a garden?
  • Where do you get fruits and vegetables from?
  • What season is best to buy certain fruits and vegetables?

Getting Students Excited

I will bring in a variety of fruits and vegetables for the class to eat. As they are eating I will ask them if they notice any fruits and vegetables that are not here to taste. Why are they not here? We will discuss seasons of harvesting, pricing, transportation of fruit and vegetables and where to buy in season produce.

I will hand out many packets of seeds. I will ask the students to take a look at the back of each packet. On the back of each packet is a map that shows what area we are in and what is a good time to start planting the seeds that we are looking at. I will have the students look at all of the packets to determine which seeds are good for planting in our area and in the spring time. I will ask the students to write those seeds on the board that we can plant in the spring. As a class we will select as many seeds as we have space to grow in our school community garden.

Once we have planted our own garden we will start talking about how we can build a garden to help our community members that cannot afford to buy fresh produce all of the time or would benefit their cause(food kitchens). Students will then start to research who in the community helps others and who in the community needs our help with a fruit and vegetable garden.

Planting a Garden

  • What do we need? (soil, seeds, water, sunlight and space)
  • Spacing the seeds
  • Taller plants to the north so the smaller plants can reach sunlight
  • Garden care
  • When to harvest

Where to buy Seasonal Fruits and Vegetables

  • Farmers Market 4th Street
  • Summer – Farmers Market at City Hall
  • Bountiful Baskets – Pickup is at Knoles and Cromer Elementary Schools
  • Grocery Stores

How do you know it is in season?

  • Price – low price or on sale it is in season, high price it is not in season
  • Availability (may not be in stores)

Community Garden

  • Who can benefit?
  • Ask friends and neighbors
  • Ask community leaders
  • Search the internet

Fruits and Vegetables that grow well in Flagstaff

  • Strawberries
  • Tomatoes
  • Cherry Trees
  • Cucumbers
  • Varieties of squash
  • Varieties of spices
  • Watermelon
  • Potatoes
  • Green Beans
  • Corn
  • Eggplant
  • Turnips
  • & so much more

Sub-Unit Activities
All Activities Should Be Performed in Sequential Order.

  • Students can make a hypothesis about the size and shape of each fruit and vegetable seed. Students will then dissect their fruit and vegetables and distinguish if their hypothesis matched what they really see.
  • Students will create their own garden map. They will decide what to plant, where to plant, the shape of the garden, and placement of seeds.
  • Students will plant seeds that are not seasonal to our area and/or climate (pineapple). They will make their own theories about the seeds (will it germinate, will it grow, how long will it take to mature, etc…)
  • Class will go to the Farmers market for a field trip and see what is in season. They will learn about price, distribution and local farmers. Class will then visit a local grocery store with their families. There they will look at the different produce and see if they can tell if it is a product that is in season or not. They will discuss with the class their findings.
  • When the class garden is ready for consumption, the class will have a garden party. The students will create a menu using what they have grown. They will create recipes with their fruits and vegetables, make the food and share. (This can be a group effort.)

Images that can help teacher provide examples to their students


Tomato Plant


Seed Spacing


Community Garden

An approach that a teacher could take to get children engaged in sustainability with a focus on gardens, plants, and ecology would be to create a class garden. Teachers could start this unit by teaching students about compost piles and give them instructions on how to make their own. Students would select the vegetables, fruits, and/or plants that they would like to grow in their class garden. Students would need to learn about photosynthesis as well as how to care for their seeds and/or plants. When all of the produce is fully matured, the class could decide how to harvest and prepare the produce for consumption.

A way to engage students in the process of photosynthesis would be to place a plant in a glass container full of water in direct sunlight and observe the bubbles of oxygen that are being released from the plants and that rise to the surface. Students could create and test their own hypotheses by observing the color ofplants, and therefore the amount of chlorophyll, to see if more color (green) creates more photosynthesis activity in the plants and their environments. Students could engage in the seed life subunit by observing the different stages in the plant life cycle and comparing and contrasting the seeds verses sprouts under a microscope. Students will also become engaged through observing different sprouts and creating hypotheses about which plants the sprouts belong to. Students will be engaged through hands-on activities by planting their own seeds to take home. Students will be able to select their produce choices by tasting samples of locally available options of vegetables. Students will be encouraged to talk to their families about creating their own composts and gardening systems at home. Inquiries are mostly student-directed. Students will be asked for their ideas and background knowledge. Students will explore their own ideas by generating their own theories and hypotheses and test them through observation and experimentation. Teachers will provide guidance for the students.

An end goal that students could work towards for this unit would be to create a community garden that would benefit the underprivileged in the community. Such places include retirement homes, shelters, and other volunteer agencies. Students could share their knowledge about sustainability within their school and with the greater community by writing a letter to the city newspaper editor explaining what they learned about and accomplished as well as why sustainability is important for the future of life on Earth.

Sustainability can be used to explore other subjects such as social studies and language arts. Sustainability is a huge social studies topic because it relates to the larger global impact on our environment. It touches on recycling through the use of compost, the respiratory cycles and plant cycles, and the use of carbon dioxide and oxygen. Sustainability also teaches children how to rely on locally grown produce and not other sources for food. Children could gain an understanding of global trades of food, especially produce, through export and import. Teachers could extend this topic into history by having students research how farming has changed and developed throughout the years into the industrialized process that it is today. Sustainability could be used in language arts because students could research through reading different texts and writing through documentation of their experimental and observational inquiry. Students could use mathematics as a natural part of this unit by figuring out how to structure their gardens. This includes the depth of seed plantation, spacing of seed rows, and length and width of the whole garden. Students could incorporate art by mapping out their garden designs. Students could explore the metapatterns that are present in the plants and seeds including the cycles present in plant life and the sustainability process. Students could also observe the patterns present in grown produce and create their own theories about why each produce has the shape that it does.


Cucumber Seed Stages


Plant Part Names

This unit will have no summative assessment portions at all. Each child will individually be assessed through formative and authentic assessment which will be accomplished through observing students and interacting with them while they are actively engaged throughout the unit.

We will obtain background knowledge from the students before the unit by asking the following questions:

  • Do you know what photosynthesis is?
  • What do you know about seed and plant life cycles?
  • How many of you have ever planted your own plants, whether it’s flowers, vegetables, etc.?
  • Do you know where you can buy locally grown produce here in Flagstaff?

During the unit, we will be interacting with the students throughout the various activities. We will be observing the students as they learn about photosynthesis and the respiration cycle, complete the cycle handout, play the matching the seeds game, learn about the seed cycle, and learn about gardening. We will listen to the student’s conversations with their parents and their peers to check for understanding. At the end of the unit, the students will announce their findings about sustainability in relation to gardens, plants, and ecology to their class and/or school in order to encourage other students to plant their own gardens and buy local produce.

This is our Sustainability: Gardens, Plants, and Ecology station at Exploring Your World Day. At this station, children were able to learn about the photosynthesis and respiration cycle, the seed life cycle, match seeds to their corresponding plant and sprout, look at seeds sprouting through the microscope, and taste the end products of locally grown cucumber, tomatoes, and beans in bean dip.


A child is watering their tomato seeds.


A child is having fun matching the seeds to their plant pictures and sprouts.


Here, a child is observing the process of photosynthesis in action.


A child is looking through the microscope and observing the sprouting of a bean seed.


A happy customer poses with her planted vegetable seeds.

Our activities were effective in engaging children in inquiry and learning because all of the activities were hands-on. Each child was able to move from activity to activity, creating their own hypotheses and testing them. In order for things to have been done more effectively, students could have been asked to come up with their own experiments and inquiry activities in order to have a higher level of engagement from the students. In order to address the needs of different populations of students, we could have made the planted produce meaningful to the student’s heritage. For example, Native Americans are known for growing crops such as corn, squash, and beans. We could also extend this lesson by having traditional Native Americans come in and talk about the importance of their crops. In doing this, discussions could open up on agricultural needs for individual tribes versus mass populations.


Bloom, J. W. (2011). The Really Useful Elementary Science Book. New York, NY: Taylor & Francis Group.

Bloom, J. W. (2006). Creating a Classroom Community of Young Scientists: Second Edition. New York, NY: Taylor & Francis Group.

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