Reference home / Curriculum / 3A / Chapter 2

Grade 3 · Semester A

Chapter 2 · Addition and Subtraction — Part 1

Original lessons, consolidation, and practice assessments.

This original chapter develops addition and subtraction — part 1 through concrete representations, diagrams, and abstract calculations. The lesson order follows the public Dimensions Math 3A topic sequence; exercises and explanations are independently authored.

10lessons
2consolidations
34review questions
22exam questions

Advanced learners may test ahead, but should still demonstrate conceptual reasoning and unfamiliar problem solving.

Lesson pathway

01
Mental Addition — Part 13A-C02-L01 · concept, examples, practice, exit check
→02
Mental Addition — Part 23A-C02-L02 · concept, examples, practice, exit check
→03
Mental Subtraction — Part 13A-C02-L03 · concept, examples, practice, exit check
→04
Mental Subtraction — Part 23A-C02-L04 · concept, examples, practice, exit check
→05
Making 100 and Making 1,0003A-C02-L05 · concept, examples, practice, exit check
→06
Strategies for Numbers Close to Hundreds3A-C02-L06 · concept, examples, practice, exit check
→
Practice AConsolidate earlier lessons →
07
Sum and Difference3A-C02-L07 · concept, examples, practice, exit check
→08
Word Problems — Part 13A-C02-L08 · concept, examples, practice, exit check
→09
Word Problems — Part 23A-C02-L09 · concept, examples, practice, exit check
→10
2-Step Word Problems3A-C02-L10 · concept, examples, practice, exit check
→
Practice BConsolidate later lessons →

Review and verification

Chapter reviewMixed questions spanning every lessonPractice examinationFresh original questions; untimedComplete solutionsAnswer reasoning for all questions

Mastery requirements

Demonstrate accurate calculation, an explanation connected to a useful model, independent application, and delayed retention. A high routine score alone does not establish transfer.

These public resources are supplemental learning materials and are not publisher placement examinations.