FoodCorps Lesson: Garlic Multiplication
Your Name: Melissa Tinling
State where you are serving: North Carolina
Ages/Grade Level: 3rd +
Subject Area: Math
Lesson Time: 30min. – 1hr.
Learning Objectives: Common Core: 3.OA.4, 3.OA.5, 3.OA.7
Prep Time: (5 min.)
- Garden journals
- Heads of seed garlic
- Jar of garlic salt or minced garlic
- Small dish
- Watering supplies (cans, buckets, cups, etc.) www.rickertville.com
- Optional, gardening gloves
Garlic is in the same family as onions and lilies. It originated in Asia. We eat the bulbs, which are part of the roots. In Spanish, a clove is called a tooth, “el diente”. In North Carolina we can plant garlic in the fall and harvest it in the late spring or early summer. Shoots will pop out in fall, remain dormant all winter, and resume growth in the spring. Planting depth is 2-3”. Spacing between cloves is 6-8”, or closer if you plan to pull out every other shoot in the early spring to eat as “green garlic” (like green onions, with a mild garlic flavor). Some varieties will send up a flowering head called a “scape”- you can eat those, too! Be sure to pull them out or the plant won’t put enough energy into the bulb.
Opening: (5 min)
- Pass around a dish of garlic salt and have students smell and guess what plant it is. Encourage them to think what the smell reminds them of.
- Who knows what foods we eat have garlic in them? → think pair share.
- Show a head of seed garlic. Open to show cloves. Emphasize vocab words: head and clove. Point out the root and the stem.
- Explain that each clove is like a seed, you plant it in the ground and it grows into a whole round head. (Note- the cloves must be planted stem up and root down, otherwise they won’t grow).
Lesson Activity: (20 min)
Farmers use a lot of math when planning their crops. We also need math in our garden to figure out (how much will fit in our garden / how much to plant / how much to save for next year / etc.)
Students work in groups with white boards or independently in notebooks.
Option 1 – calculate how much can fit in your garden (outside):
- Measure the length and width of the garden plot using rulers.
- Use more rulers or string to make a grid on top of the soil so students can visualize the concept of square feet.
- Multiply LxW=A to determine how many square feet are in the plot.
- Each square foot can fit 4 garlic plants. Multiply Ax4 to determine the total number of cloves that can be planted.
- Count out that many cloves of garlic together or in groups.
- Demonstrate to students proper spacing of the four cloves. Start off doing it wrong – e.g. in the corners of the square – and have students help determine proper spacing.
- Students lay out cloves, 4 to each square.
- Remind students again of the root and the stem. Once the cloves are positioned correctly, students push them in 2-3” deep.
- Remove rulers. Mulch the plot with hay or leaves and water it.
Option 2 – calculate how much to plant this year and next
1. Math problem (inside):
- Count cloves inside the head.
- If we plant X cloves today, how many HEADS will we get? (X*1=X)
- How many CLOVES will we get? (X*X = X2 = Y cloves).
- Optional: take it out more years (exponentials). Next year if we plant Y cloves we’ll get Y2, etc. (depending on level of students)
- What if we decide to sell our garlic? Let’s sell them for $M. (R heads * $M = MxR)
- Well, we shouldn’t save it all- we should eat some, too! How many should we eat? Decide together. Example problems:
- If we eat Q cloves, how many cloves will be left to plant?
- Rats got into our barn and ate R cloves. Now we have?
- So how many heads will we grow next year?
Example: 8 cloves per head. Let’s plant one head. [8 x 1] = 8 new heads. That’s [8 x 8] = 64 cloves. If we want to get 16 heads NEXT year, we should save [16 heads / 8 cloves per head] = 2 heads. So that leaves us [8 heads – 2 heads] = 6 heads left over to eat (or [6 x 8] = 48 cloves to eat). But if we sell them instead of eating them, we could make $2 * 6 = $12!
2. Planting (outside):
- Students work together to drag a stick down the plot to make a row.
- Students line up rulers or tape measure along row and stick one ruler vertical every 6 inches (counting by sixes!)
- Show how to identify the flat end and the pointy end of the clove
- Model how to plant with the stem end up.
- Students work in pairs to plant a clove at each marked spot.
- Add dried leaves on top or other mulch.
- Water gently.
Wrap up (5 min)
- Boy, farmers sure do have a lot of math to do! It’s not just for garlic- for everything they want to grow, farmers first have to multiply and divide and add and subtract to find out how many seeds to buy, how many seeds to plant, how many seeds to save, and how many seeds to sell!
- We are going to observe our garlic all through winter and spring until we harvest it. When we observe, we always record observations (write down what we did, what we see, etc. in our notebooks)
Have students write, illustrate, and date the first garlic entry notebooks.
- Cook and/or eat something with garlic. One easy example is garlic bread: squish garlic through a garlic press and mix with olive oil and salt and pepper on a plate. Slice bread into rounds and “mop” up the oil mixture. Bake at 350° on a cookie sheet until golden brown!
- ELA: read a famous Jewish folk tale about greed and garlic: http://www.publishersweekly.com/978-0-8234-1222-8. (On YouTube, 4 min): https://www.youtube.com/watch?v=7jAR4XlhP4E
- Measure your garlic plant every week from when you plant it until harvest time, and plot the growth on a chart.
- Plant a clove inside a clear plastic cup filled with soil, against the side. Watch it grow in real time inside your warm classroom!