1. MeasureEstimating Metric Length Unit of Study: Length in Metric Global Concept Guide: __2_ of __3_

2. Content Development  Through direct comparison, children will first determine whether the object is longer or shorter than the object with the known length. Then using direct comparison children estimate how much shorter or longer the object with the unknown length is.  Using this strategy students are better able to make reasonable estimates.  When students are asked to select the best unit for measuring they need to connect the inverse relationship between the size of the unit and the number of units used to measure the length.  For example when asked to measure the distance from home to school the number of meters would be much less than the number of centimeters. They could both be used but meters would be the more practical choice.

3. Day 1  The focus of this day is for students to gain a better understanding of how to use known lengths to estimate the length of an unknown using the centimeter unit.  There are lesson components in GoMath Lesson 9.2 that are listed in the lesson ideas on the GCG to pull from for this day.  You may want to give the student a ten rod, which is approximately 10 cm long. This will act as a “known” length to use to guide their estimated lengths of unknowns.  In the lesson activities on the GCG you could use the “Estimate Length in Centimeters Chart” to guide students in estimating lengths in centimeters. Then measuring them to confirm if they are accurate or not. Note: you may need to change the listed objects to fit your classroom

4. Day 2  The focus of day 2 is estimate the length of objects in meters. Students should be encouraged to use objects that they know are about 1 meter long to estimate the lengths of unknown objects.  There are lesson components in GoMath Lesson 9.6 that are listed in the lesson ideas on the GCG to pull from for this day.  In the lesson activities on the GCG you could use the “Estimate Length in Meters Chart” to guide students in estimating lengths in meters. Then measuring them to confirm if they are accurate or not. Note: you may need to change the listed objects to fit your classroom  The graphic below may be used to help students remember length and width.

5. Day 3  The focus of this day is for students to estimate lengths in centimeters and meters. Students will need to determine which unit of measurement is most appropriate to use when estimating.  Students will need to have discussions justifying their reasoning for choosing meters of centimeters.  The students should be exposed to both real world measurments as well as paper and pencil examples. Listed in the lesson ideas section of the GCG is “Estimate Using Centimeters and Meters” to assist students in measuring objects relying on background knowledge.

6. Enrich/Reteach/Intervention  Enriching Activities-Enrich T.E. p 437B, Enrich page E87, Enrich page E91  Reteach Activities-Reteach pages R87 and R91. In the Lesson Ideas on the GCGs there is a link to “Learn to Estimate” that could be used to remediate students.