Beacon Lesson Plan Library

Mammoth Sunflower Problem

Frieda Bates
Santa Rosa District Schools


Students use information on a package of seeds to practice measurement and solve a real-world problem.


The student translates problem situations into diagrams and models using whole numbers, fractions, mixed numbers and decimals to hundredths including money notation.


-Package of mammoth sunflower seed for each group
-Paper (yellow construction paper is a good option)
-Transparancies and markers
-Student calculators (optional)
-Yarn or string


Gather materials


1. Divide the class into small groups.

2. Review the purpose of seeds and discuss what a seed would need to grow. At some point in the discussion, room to grow should be mentioned.

3. Provide the groups with a pack of seeds and give them time to read the information and discuss it in their small group setting.

4. As a whole class, encourage the groups to share their observations concerning the information on the outside of the package. Ask students to justify the inclusion of the information observed. For instance ask,-Why would the seller of this product want you to know that this plant grows best in full sun?- or -Why would the company provide an 800 number to the consumer?-

5. After this discussion, direct the studentsí attention to the portion of the packet that gives directions concerning spacing of seeds. Normally this section will provide a range of distances that would be appropriate. Discuss with the students why a range of spacing suggestion is provided instead of a set distance.

6. As a group, ask the students to agree on a spacing distance for their seeds.

7. Have the groups open the packets and count the number of seeds.

8. Have each group write an equation to determine the length of the row they would need to prepare. For instance, if the group agreed 18 inches would be appropriate for spacing and their package contained 50 seeds, their equation would be 18x50=L . -L- would be equal to 900 inches. (You may wish to distribute and use calculators.)

9. Have the students write another equation that will convert the total number of inches to feet and inches. You may need to remind them that there are 12 inches in a foot. Using the earlier sample, 900 divided by 12 would give them 75 feet. There seeds would require 75 feet of growing room.

10. Review the use of yardsticks.

11. Give each group a yardstick and string. Instruct each group to measure a length of string that would be the same length as the row they would need to have to plant their seeds. (You will find that many of them will be amazed when they see how long this really is!)

12. At this point you will probably want to take your class outside so they can stretch out their -rows.-

13. Then, point out that many people choose not to plant their seeds in one long row, but to divide their seeds so that they will have several shorter rows. Instruct each group to determine how many shorter rows they would want. Have them write and equation to show the length of each shorter row.

14. Now, have them cut their string to show the length of their new rows.

15. Have the students return to the classroom. Discuss with them that many gardeners like to sketch out a plan for their gardens.

16. Hand out the (yellow) paper. Instruct them to sketch their groupís plan for their sunflower garden. Instruct them to include information including: the number of seeds, spacing distance between the seeds, and the length of each row. Depending on the group, you may wish to demonstrate on the overhead.


NOTE: This lesson only assess a portion of the benchmark dealing with whole numbers. Assess that students have worked in small groups and determined a viable plan for planting their seeds. Mastery or non mastery will depend on whether or not students complete 2 out of 2 equations and a sketch (plan) that contains the number of seeds, distances, and lengths. This should be done with at least 80 % accuracy.


The teacher may chose to use graph paper and have students draw the garden to scale. Or, you may wish to involve the planning of more than one type of seed.
(Digging up the school grounds may or may not be deemed appropriate, so students may wish to plant their seeds in containers to take home.)

Web Links

Free Seeds and a coloring page.

Return to the Beacon Lesson Plan Library.