@internet4classr I4C

## CCSS.Math.Content.1.NBT.C.5 - Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.

Authors: National Governors Association Center for Best Practices, Council of Chief State School Officers

Title: CCSS.Math.Content.1.NBT.C.5 Given A Two-digit Number, Mentally Find 10... Number and Operations in Base Ten - 1st Grade Mathematics Common Core State Standards

Publisher: National Governors Association Center for Best Practices, Council of Chief State School Officers, Washington D.C.

(Page last edited 07/25/2017)

1. I4C: Online Practice - Find 10 less, given two-digit number - These online practice quizzes (interactives) support the following Common Core State Standard: CCSS.Math.Content.1.NBT.C.5. There are 100 quiz sets available on this topic. Answers are corrected after each question and a quiz results page is also shown which can be printed or emailed to a teacher, parent or mentor.
2. I4C: Online Practice - Find 10 more, given two-digit number - These online practice quizzes (interactives) support the following Common Core State Standard: CCSS.Math.Content.1.NBT.C.5. There are 100 quiz sets available on this topic. Answers are corrected after each question and a quiz results page is also shown which can be printed or emailed to a teacher, parent or mentor.
3. I4C: Printable Worksheets - Find 10 less, given two-digit number - These worksheets support the following Common Core State Standard: CCSS.Math.Content.1.NBT.C.5. There are 100 worksheets available on this topic. A master answer key is available.
4. I4C: Printable Worksheets - Find 10 more, given two-digit number - These worksheets support the following Common Core State Standard: CCSS.Math.Content.1.NBT.C.5. There are 100 worksheets available on this topic. A master answer key is available.
5. 10 More or Less - Online quiz; type in the missing answer.
6. 100 Hunt Addition - Online Game; look at the number given, add 10 and click on the answer.
7. Add or Subtract Whole Tens Mentally - Online lesson; Add or subtract whole tens mentally; good for whole class activity.
9. Adding 10 DepthCharger - Online game; once the robot has landed, click on the problem below in the little box and then add 10 to the depth level to destroy the robot.
10. Adding Three Numbers - Find the sum of the three numbers.
11. Less and more - Printable; answer the questions using the 100 chart.
12. Subtracting Tens - Online timed quiz; find the answers to these problems.
13. Tasks to show off learning of these skills. - Worksheets; multiple problem examples and worksheets
14. Ten Sweets Per Pack - Video, visual explanation of this concept.

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