Objective Students will be able to estimate sums and differences (3-5).

Vocabulary Clustering- method used to estimate decimal sums and differences by rounding a group of #’s to the same whole #.

Steps: Estimate using rounding: * Read all directions!!!!!! * When a whole # is given, round to the nearest whole #. * When a decimal is given without a whole #, round to the nearest tenth. * After rounding, add or subtract to get final answer.

Steps Con’t. : Estimate using clustering: * Read all directions!!!!!! * Look at given #’s. * Round all #’s to the same whole #. Be careful to look at all #’s before choosing the correct #. * After rounding, add or subtract.

Remember: If money is involved, round to the nearest dollar amount.