Excerpt 3: Geometric Measurement in Grade 1 (Pages 8-11)

Description: One of a series of documents describing the progression of a topic across several grade levels, informed both by research on children's development and by the structure of mathematics. First graders should continue to use direct comparison-carefully, considering all endpoints-when that is appropriate. Once they can compare lengths of objects by direct comparison, they could compare several items to a single item, such as finding all the objects in the classroom the same length as (or longer than, or shorter than) their forearm.