Find How Many Were Added
Write start + unknown = finish.
About 15 minutes, plus any extended practice
Open lesson 1Find Unknowns in Addition and Subtraction Stories
Represent a missing change, a missing start, a comparison, and a balanced equation.
Before you begin
- Add and subtract within ten; count to twenty.
Choose by skill rather than age alone. Read with an adult when useful, revisit a lesson, or explore another grade.
Follow the lesson sequence
Find a Starting Amount Before Some Leave
Write start − removed = remaining.
About 15 minutes, plus any extended practice
Open lesson 2Find How Many More in a Comparison
Make matching pairs between the two supplied counts.
About 15 minutes, plus any extended practice
Open lesson 3Find the Number That Balances an Equation
Calculate the complete side and keep that total visible.
About 15 minutes, plus any extended practice
Open lesson 4Review and transfer
After the lessons, try 4 new review cases and a practical task. Each answer has an explanation and a link back to the related lesson.
Open the unit reviewGuest answers are temporary. Keep your own paper or document; this unit does not certify completion or record a school grade.
Topic references
- Common Core State Standards, mathematics: 1.OA.A.1 — Represent a missing change, a missing start, a comparison, and a balanced equation.
- Common Core State Standards, mathematics: 1.OA.D.7 — Represent a missing change, a missing start, a comparison, and a balanced equation.
- Common Core State Standards, mathematics: 1.OA.D.8 — Represent a missing change, a missing start, a comparison, and a balanced equation.
These references informed the topic selection. They do not certify complete standards alignment.