Estimation and Pattern Discovery

Overview After collecting a ripened sunflower head from their rooftop garden, students estimate its seed count by discussing and applying several strategies. They graph estimations on a line plot and use calculators to find and compare the actual total. Students also research a mathematician on the Internet and make collages of sunflower models that they present to senior citizens.	For more about this special from Rooftop Garden ~Planting Seeds of Service, e-mail Lai Lai Sheung, author and AT&T Teacher Disseminator.
Learning Standards Learn to problem solve, communicate, and reason strategies used in estimating large numbers. Identify and describe a variety of patterns in nature.
Classroom Activities Students closely examine a sunflower head filled with seeds and a single sunflower seed. Discuss estimation strategies. Volunteers measure an area of up to ten seeds and determine total count. Each student estimates total seeds and records answer on round self-sticking labels. Prepare line plot - a graph that looks like a number line - on mural paper. Draw a number line from one to five hundred. Label line at intervals of fifty. Affix labels with estimations on line plot above corresponding numbers. For duplicates, place second label above first estimate.	Volunteers remove seeds from sunflower head and use calculators to count them. Compare total seed count with estimates. Student pairs observe natural growing pattern of seeds. Use an oak tag worksheet to make a sunflower model. Starting from innermost circle, glue sunflower seeds onto sheet. Record number of seeds used and describe observed patterns. Compare pattern results of seeds in models with those in real sunflower head.
Community Activities Students make a sunflower collage from worksheet models and present it to neighboring senior center.	Careers Students search the Internet for information on Leonardo Fibonacci who first observed special number patterns in nature. Discuss math careers: accountants, computer programmers.
Materials A few sunflower heads (if unavailable from garden, purchase from florist or bird store), mural or chart paper, round self-sticking labels, oak tag, markers, two lbs. of dried sunflower seeds, glue	Technology Students work with calculators to total the sunflower seeds and use Internet to research numbers in the Fibonacci sequence.
Assessment Given a sunflower head of similar size, students estimate total seeds; they also, estimate the number of seeds in sunflowers with larger or smaller diameters.	Web Sites Students locate encyclopedia website Encarta and read about the Fibonacci Series.