In this unit, students explore length comparisons both directly and indirectly. They build and expand upon the direct comparison that they learned in Kindergarten. Students in Grade 1 should be able to extend this prior knowledge to make comparison through the use of a third object. Students may compare incorrectly because the endpoints are not lined up or the unit being used to measure is not in a straight path.
Key Concepts:
 Comparing lengths of objects requires taking both endpoints into account.
 If object A is longer than object B and object B is longer than object C, then object A is longer than object C.
Prior Knowledge Needed:
 Describe measureable attributes of objects, such as length or weight. (K.MD.1 D)
 Directly compare two objects with a measurable attribute in common, to see which object has “more of”/”less of” the attribute, and describe the difference. (K.MD.2 D)
 Classify objects into given categories; count the numbers of objects in each category and sort the categories by count. (K.MD.3)
Units on the Horizon:
 Measure lengths indirectly and by iterating length units; (Grade 1, Unit 16: 1.MD.A.2)
 Relate comparing with difference unknown problems; (Grade 1, Unit 9: 1.OA.A.1)
Lessons

Lesson objective: Extend prior knowledge about comparing two objects and developing the understanding that comparing lengths of objects requires taking both endpoints into account. Throughout the lesson, students will extend this knowledge to include co...

Lesson objective: Extend prior knowledge about comparing two objects and develop the understanding that comparing lengths of objects requires taking both endpoints into account. This lesson helps to build understanding that comparing lengths of objects ...

Lesson objective: Compare lengths of objects both directly and indirectly. Understand that if object A is longer than object B, and object B is longer than object C, then object A is longer than object C. Students bring prior knowledge from K.MD.2 Dire...

Lesson objective: Compare lengths of objects both directly and indirectly. Understand that if object A is longer than object B and object B is longer than object C, then object A is longer than object C. This lesson helps to build fluency with comparin...

Lesson objective: Students explore length comparisons both directly and indirectly . This lesson provides an opportunity for students to apply their knowledge and understanding of length comparisons both directly and indirectly. They extend their knowle...