Common Core
1.NBT.C.4
8 lessons teach this standard. Every lesson is interactive, and every one prints as a worksheet with a separate answer key.
Grade 1 Math · Chapter 8 · Lesson 1
Add whole tens the same way you add ones.
Grade 1 Math · Chapter 8 · Lesson 3
Add whole tens and watch the ones stay put.
Grade 1 Math · Chapter 8 · Lesson 4
Adding Ones Without Making a New Ten
Add a small number when the ones still fit.
Grade 1 Math · Chapter 8 · Lesson 5
Use the make-ten move on bigger numbers.
Grade 1 Math · Chapter 8 · Lesson 8
Add tens to tens, then ones to ones.
Grade 1 Math · Chapter 8 · Lesson 9
Sometimes the ones fill up and you need a new ten.
Grade 1 Math · Chapter 10 · Lesson 7
Adding to 100 With Place Value
Add bigger numbers by adding tens to tens.
Grade 1 Math · Chapter 10 · Lesson 8
Make a new ten with bigger numbers too.