lesson
Finding 10 More and 10 Less Mentally
Mentally add or subtract 10 from a two- or three-digit number.

Mentally add or subtract 10 from a two- or three-digit number.
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5 lessons
Identify and explain even and odd numbers using pairs, and mentally find 10 or 100 more/less and estimate quantities in everyday situations.
select tools, including real objects, manipulatives, paper and pencil, and technology as appropriate, and techniques, including mental math, estimation, and number sense as appropriate, to solve problems;
analyze mathematical relationships to connect and communicate mathematical ideas; and