Yesterday my mind (and heart) were on the gulf shore. In retrospect I realized that I could have shared more literature suggestions and teaching ideas about estimation, so we will revisit the topic today.
Stuart J. Murphy offers a nice overview of estimation with Betcha! Teachers can replicate activities such as estimating the number of jellybeans, or other objects, in a jar to give students the opportunity to hone their own estimation skills. Another Murphy title, Coyotes All Around, introduces the concept of rounding to estimate.
Discuss real life situations where estimation is appropriate compared to when an exact answer is necessary. The Counting is for the Birds problem, from the February 2010 issue of Teaching Children Mathematics presents an interesting estimation challenge and two estimation strategies.
Sample solutions were published in the February 2011 issue.