Importance of Estimation

Estimation
Based on the book, Greater Estimations by Bruce Goldstone
Mathematics
Grade 3 – 6

Objectives
Students will establish benchmarks or standards for determining how much or how many of something.
Students will use estimation strategies of eye training, clump counting and box and count.

Activities/Projects
Students will practice using estimation techniques utilizing the photos in Bruce Goldstone’s book Greater Estimations. Working in groups of 3 – 4, students will read through the book, focusing on the example photographs up to p. 21. The teacher will circulate among the groups to facilitate the use of strategies and establishing benchmarks for reasonable guesses of how many and how much. (Ideally one book per group is needed, however the activity works with one book and teacher leading the discussion.)

Students will then use digital devices to create “estimation photos” from their own environment. Students will have the option of working alone, in pairs or small group. Photos will then be uploaded on to a “wiki” for classmates to view and post “guesses.” Students will be responsible for responding to posts made to their picture post.

A related but separate activity will branch off the estimation of tangible things. The teacher will have the students close their eyes for an amount of time. The students will then guess how much time passed. After a brief discussion, ask students to estimate how long they think 1 million seconds is? In a separate section of the wiki students will post their estimations. Students will then be encouraged to collaborate through the wiki discussion board to revise their estimates and settle on a reasonable estimate based on mathematical discussion. . (60 seconds = 1 minute = 1 hour. 24 hours = 1 day. 7 days = 1 week, apx. 4 weeks = 1 month, 52 weeks = 12 months = 1 year)


Websites:
http://www.estimationphotos.wikispaces.com/


Assessment
Althoughthe initial activity will be completed in 1 block, participation in the wiki will be ongoing and done outside of class. Students will be required to post their photo within 2 days of initial instruction and contribute to the discussion board regularly. In their posts students must use mathematical language and refer to the estimation strategies to further explain the reasonableness of their responses. A performance rubric will be used.