Organizer
Curated OER

Counting and Calculating

For Students 1st - 2nd
In this math worksheet, students follow the basic activities that are shown in the planning guide written for the teacher. The plan is written in the form of a unit.
Worksheet
Curated OER

Multiply Decimal Fractions by 10 or 100

For Students 4th - 5th
In this decimal fraction multiplication worksheet, students read an explanation of rules, then solve 24 problems. Answers are included on page 2.
Worksheet
Curated OER

Mental Math Strategies

For Students 3rd - 4th
In this mental math worksheet, students study the detailed instructions and examples for adding or subtracting numbers using "breaking apart" or compensation. Students solve 17 mental math problems.
Unit Plan
Khan Academy

Khan Academy: Adding Two Digit Numbers by Making Tens

For Students 1st - 3rd Standards
In this exercise, students practice adding two-digit numbers by making tens. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
Unknown Type
Khan Academy

Khan Academy: Add 2 Digit Numbers by Making Tens 2

For Students 2nd - 4th Standards
Practice adding two-digit numbers by making tens on Khan Academy. If you are stuck, watch a refresher video or choose to get a hint. Test yourself to see how many you can get correct!
Unknown Type
Khan Academy

Khan Academy: Add 2 Digit Numbers by Making Tens

For Students 2nd Standards
Students will be challenged in their skills to add 2-digit numbers by making tens
Lesson Plan
Better Lesson

Better Lesson: Magic of Adding Tens

For Teachers 2nd Standards
Can your students make bundles of tens? This lesson allows students to visualize adding tens to make one hundred.
Interactive
PBS

Pbs Kids: Curious George's Busy Day: Museum of Tens Game

For Students K - 1st
Each display in the museum has 10 items in it, but some are missing. How many do you need to add to make 10? Can you do the math?
Activity
Illustrative Mathematics

Illustrative Mathematics: Peyton and Presley Discuss Addition

For Teachers 1st - 3rd Standards
The purpose of this task is to support students in developing an understanding of a place value strategy for adding numbers. By using a representation to visualize the abstract notation, students will make sense of the strategy, adding...