lesson 1. classroom discussion and activity: predict and

Curriculum Enhancement Options: •  Seed Plants video (Brain Pop, 2014).

Key Words: •  Germination is the first stage in the process by

which a plant grows from a seed. •  Hypocotyl is the stem of a germinating seed. •  Legumes are plants in the Fabaceae family that

grow fresh or dry seeds in pods, and form a symbiotic relationship with nitrogen-fixing bacteria on root nodules.

•  Photosynthesis is a process used by plants to

convert light energy into chemical energy for plant growth, root development, flowering, and seed production.

•  Predict is an estimation or statement about the ways things will happen in the future, often based on knowledge or experience.

•  Radicle is the first part of a seedling to emerge

and is the young root of the plant.

Time required for discussion and activity: 1-3 hours. Follow up: •  See bottoms of page 4. Materials: For each group of students •  3 plastic bags (sandwich size) •  3 paper towels (thick paper towels that hold

water) •  9 beans of the same kind (e.g. all black or all

orca beans) •  Permanent markers •  Water for wetting paper towels •  Student Handout: Predict and Observe Seed

Germination, 1 per student

Germination

Lesson 1. Classroom Discussion and Activity: Predict and Observe Seed Germination

School Garden Curriculum vegetables.wsu.edu/schoolgarden/ 4

SPRING or FALL

Learning Targets: •  How do water and sunlight affect a seed’s

ability to germinate? Success Criteria: •  I can predict how water and sun affect the

seed’s ability to germinate. Big Idea: Plants use energy from the sun to make food from water and air.


Instructional Process

Science journal options: o  Record the key points throughout the lesson. o  Predict outcome of experiment and reasoning for their prediction. o  Draw a schematic of the experiment (e.g., draw each bag and describe the different

environments). o  Make observations throughout the experiment.

Engage Students by showing them bean seeds and asking them what ways they eat them. Step 1. Dry beans are a model crop for biology and nutrition. Background information: Dry beans are a model crop for school garden curriculum because they are: •  A healthy food choice:

o  A protein source that is easily stored without further preserving. o  An excellent source of dietary fiber. o  Contains little to no fat.

•  Biologically, beans are an interesting plant to grow and study:

o  Pods house seeds which have beautiful color patterns. o  Roots have nodules, which are the site for nitrogen fixation.

Ask students Ø  Why are plants important for people and what do plants need to grow?

•  Record their ideas for all to see. •  Add any information missed by students from list below.

Background information: Plants provide: •  Nutrition and medicine � Beauty for landscapes •  Oxygen into the atmosphere � Soil retention •  Habitat for animals, birds, and insects � Fiber for clothing Background information: In these three lessons, we will be learning about pulse crops, which are in the legume family. Legume plants fix (absorb) atmospheric nitrogen through a symbiotic relationship with bacteria in root nodules in the soil; this process is called nitrogen fixation. Legumes are also high in protein and bear seeds in pods. Pulse crops include dry beans, dry peas, garbanzos (chickpeas), and lentils. The name pulse comes from the Latin word, puls, meaning a thick soup.

Ask Students Ø  What do legume plants need to survive and

and grow? •  Record their ideas for all to see. •  Add any information missed by

students from list below. Background information: A plant is a biological system that needs sunlight, water, air, nutrients, and space for living and growing (add these points to the answers provided by students). Step 2. How a plant grows. Ask Students Ø  What do you already know about

photosynthesis? Turn to your elbow partner and share your ideas.


Background information: Green plants get their energy from sunlight in a process called photosynthesis. (Remind students that “photo” means light and “synthesis” means make). Photosynthesis is a process used by plants to convert light energy into chemical energy for plant growth, root development, flowering, and seed production Plants grow from seeds. Germination is the first stage in the process by which a plant grows from a seed. Students will conduct an experiment to determine what plants need to germinate.

Schematic of Photosynthesis


Step 3. Set up seed germination experiment: •  Organize students into groups of four or ‘table groups’. •  Give each group of students three bags and a marker. •  Tell students to label bags 1, 2, or 3, and to write their names on all three bags. •  Give each group three paper towels. Make sure paper towels are able to hold plenty of water. •  Have students fold each paper towel into fourths. •  Wet two of the paper towels. Place a wet paper towel in bags 1 and 2. Place the dry paper towel in

bag 3. •  Have students add three seeds to each bag on top of the paper towel (do not seal bag).

Ask Students Ø  Why is it important to use more than 1 seed in each bag for our experiment (Answer: to increase

our confidence in the experiment.) Ask Students Ø  Water is essential for all living organisms. What are the major ways plants use water?

•  Photosynthesis •  As a primary component within cells •  Transporting nutrients from soil into roots, then throughout the plant’s stems,

leaves and fruit

Ask Students Ø  What is the role of water in seed germination? Ø  Do you think sunlight is important for seed germination? Ø  Where can bags be placed in the room to receive sunlight or no sunlight? Step 4. Have students place bags 1 and 3 in the sun. Place bag 2 in the dark.

Step 5. Distribute Student Handout: Predict and Observe Seed Germination. Ask Students Ø  Which bag of seeds do you expect to germinate at the highest rate? Next highest? No germination at

all? Have students write their predictions on the worksheet. Step 6. After starting the experiment, check on sees 3 times within 2 weeks. Use the chart on Student Handout: Predict and Observe Seed Germination to record student’s observations for each bag.


Step 7. After the seeds have germinated, around day 5, review the outcome of the experiment and discuss the following points: Ask Students Ø  What do you observe? And why? Ø  Why aren’t the hypocotyls from seed in bag 3 green? (Answer: lack of sunlight) Ø  Why haven’t the radicles developed as much in bag 1? (Answer: too much sunlight) Ø  Which bag did the best as defined by the highest number of germinating seeds? Ø  What was it about the bag’s environment that helped the seeds germinate and grow? (Answer:

sunlight, warmth and water) Talking points: Seeds need water and warmth to germinate, while plants also need sunlight and food to grow. Soil provides plants with structural support to grow. How well soil supports a plant depends on the soil’s texture, water-holding ability, mineral content, nutrients, acidity, and population of beneficial organisms (worms, nodule forming bacteria, etc.).

Plants also need space to grow. If plants do not have enough space, they will compete with neighboring plants for nutrients, light, and, water. Under stressful conditions, plants may find it difficult to grow or survive; some will grow poorly or die. Ask Students Ø  What should we do next with these young plants to keep them growing and healthy? Ø  What happens to a plant if it is kept in a very small pot? (Answer: the plant would not grow very

big or it may even die because its roots do not have space to grow) Engage students by having them share their observations and conclusions with the class using evidence to support their conclusions, and share whether their prediction was supported or not.

On day 5, seed from bag 3 may be germinating. On day 8, seed in bags 1, 2, and 3 (from left to right) may look like this. Notice the green hypocotyl emerging from the seed from bag 1 and the radicle beginning to form root hairs in bag 3.

Predict and Observe Seed Germination

6


Lesson 2.B. School Garden Ac3vity: Count and Record Germina0on Rates

Root nodules

Time required for garden activity: 30 minutes

Materials: •  Exact-o knife •  Loupe magnifier •  Hand trowel or shovel

Lesson 1. Fall School Garden Activity:

Identify Root Nodules

FALL


Key Words: •  Nitrogen fixation is a symbiotic process

between soil bacteria and legume plants, by which gaseous nitrogen in the atmosphere is converted into a form that plants can use.

•  Root nodules house nitrogen-fixing bacteria on roots of legume plants.

•  Symbiotic relationships form between two

organisms that mutually benefit from the association.

Science journal options: o  Draw and label the root nodule(s) that you located in the root system. o  Describe the root nodules that you observed. o  Draw the root nodule that you dissected. Be sure to include the correct color. o  What color was the inside of the nodule? o  Given the need of all green plants for nitrogen, how would you describe the relationship between the bacteria and the bean plant?

Learning Targets: •  What is the function of nitrogen fixing

nodules on the roots of bean plants? Success Criteria: •  I can identify nitrogen fixing nodules on the

roots of bean plants. Big Idea: Bean plants have nitrogen fixing nodules on their roots to support growth.



Background information: •  Encouraging nitrogen fixation through the symbiotic relationship between legumes and Rhizobia

bacteria is a way farmers can add nitrogen to the soil, without the cost of purchasing nitrogen fertilizer.

•  Farmers can encourage nitrogen fixation by inoculating their seeds with Rhizobium bacterium. •  By fixing nitrogen, the plant is able to meet much of its own nitrogen needs. Plants can absorb

nitrogen in a few different forms: nitrate (NO3-), ammonia (NH3), or urea (CH4N20). Humans obtain

nitrogen by eating plants or animals that have fed on plants. •  The air is 79% nitrogen gas (N2), but plants and animals (including humans) cannot use nitrogen in

this form to make protein and nucleic acids. •  In order for N2 to be utilized to make protein and nucleic acids, the molecule must be broken apart,

which takes a large amount of energy (it can be done in the atmosphere by lighting). For bean plants (and other legumes), it is the Rhizobia that grow within the nodules on the plant roots that use their energy to assimilate N2 into plant-useable nitrogen. This biological nitrogen fixation requires a complex set of enzymes and a large expenditure of energy (ATP).

Step 1. In the garden, carefully dig up a bean plant using a hand trowel or a shovel. Look for nodules in the root system (the location where nitrogen fixation occurs).

Have students draw and label the plant roots and its nodules. Ask students Ø  What do you think a root nodule does? Turn to your elbow partner and share your ideas. Background information: A healthy root nodule will be pink to red in color on the inside, while an unhealthy nodule will be grey or white (slice root nodule in half and view the color with a loupe magnifier) Most crops require more nitrogen than any other nutrient. Nitrogen makes up the plant’s amino acids (amino acids combine to make proteins) and nucleic acids. The edible dry bean contains protein, which is made from nitrogen. However, beans do not contain all of the essential amino acids and are deficient in methionine and tryptophan. Supplement dry beans with other foods such as grains or animal protein to obtain all of the essential amino acids.


Lesson 1. Spring School Garden Activity: Plant Bean Seeds

Time required for garden activity: 15 minutes Materials: Outdoors •  Bean seed (approximately 60 seeds of each

four different varieties; 240 seeds total) •  Measuring tape •  Rulers •  Hoes •  Gloves •  Field markers •  Permanent markers

Indoors •  Bean seed (approximately 60 seeds of each

four different varieties; 240 seeds total) •  1 gal pot/bucket (3-5 per bean variety) •  Potting soil •  Trowel

Science journal options: o  Record names of different bean varieties, planting date, and the spacing and depth of seeds

planted. o  Predict the number of days it will take for germination.


Learning Targets: •  How are seeds planted? Success Criteria: •  I can plant bean seeds at correct soil depth by

measuring spacing between seeds. Big Idea: Plants need water and warmth to germinate.

SPRING

Time of year: Outdoors: Dry Beans are a warm season crop. In

northwest Washington, plant beans May 15- June 1. In other areas, plant when soil temp reaches 60 °F.

Indoors: Year-round (fall and winter require supplemental light)

Key Words: •  Furrow means a long narrow trench made in

the ground for planting seeds.



Indoors:

Background information: See Washington State University Fact Sheet: Vegetable Container Gardening (2010) for recommendations on containers, potting soil, and wateringhttp://county.wsu.edu/king/gardening/mg/factsheets/Fact%20Sheets/Container%20Vegetable%20Gardens.pdf. Step 1. In the classroom, fill a 1-gal pot or bucket (e.g., empty plastic milk container) with potting soil (3-5 pots per variety). Step 2. Measure length of potting container to prepare for planting beans. •  Using a ruler, measure spacing for 3-4 seeds (2 in. between each seed) per 1 gal container. Place field

markers (each labeled with variety name, number of seeds planted, and planting date) in the pot. •  Using a hand/finger, make a 2 in. deep furrow. Step 3. Planting bean seeds. •  Using a ruler, have students place seeds 2 in. apart along the length of the 1 gal. container. •  Using your hands, cover seeds with soil (2 in); press down on seed to ensure seed to soil contact.

Outdoors:

Background information: See Washington State University Fact Sheet: Growing Dry Beans in Home Gardens (Miles &Atterberry, 2014) http://cru.cahe.wsu.edu/CEPublications/FS135E/FS135E.pdf. Step 1. In the garden, measure length and width of bean rows to prepare for planting beans. •  Using measuring tape, measure four 10 ft (3 m) rows (one row for each bean variety); space rows 30

in. (76 cm) apart. Place field markers (each labeled with variety name, number of seeds planted, and planting date) at the ends of each row.

•  Using a hoe, make a 2 in. (5 cm) deep furrow from the field marker at the beginning of the row to the field marker at the end of the row.

Step 2. Planting bean seeds. •  Engage students by having them show their elbow partner 2 in. on a ruler or with their finger to

visualize the spacing. •  Using a ruler, have students place seeds 2 in. apart along the length of the 10 ft row (60 bean seeds

per 10 ft row). •  Using a hoe, cover seeds with soil (2 in); designate one student per row to walk (do not stomp) over

each row of seed to ensure seed to soil contact.

lesson 1. classroom discussion and activity: predict and

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