South Dakota Standards
SD.1.N. Number Sense: Students will develop and use number sense to investigate the characteristics of numbers in a variety of forms and modes of operation.
1.N.3. Develop conjectures, predictions, or estimations to solve problems and verify or justify the results.
1.N.3.1. Application: Students are able to solve addition and subtraction problems up to 20 in context.
1.N.3.1.a. Represent problem situations and solve using concrete objects, pictures, or numbers.
1.N.3.1.b. Explain how one arrives at solutions to problems.