Add three whole numbers with a sum within 20

G1.OA.21Grade 1OperationsSource mission: Flexible Addition

Adds three addends by choosing an efficient order or grouping, not strictly left to right.

Progress & proof summary

LifecycleNot started

Evidence progress0 of 2 pieces collected

Current predictionNo prediction yet

Next reviewNot scheduled

Mastery projection: Not available yetWhat does this mean?

1.OA.A.2 1.OA.B.3

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EvidencePerformanceStatusNext step

Show the stepsCarry out the procedure accurately Not startedCollect one observation

Explain the ideaDescribe why the response works Not startedCollect one observation

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Adds three addends by choosing an efficient order or grouping, not strictly left to right.

Estimated time: ~5 min