+
Worksheet
Curated OER

Mental Math: Adding 10s

For Students 1st
To develop mental math skills for adding 10s, learners read an example, solve one carefully scaffolded problem, and then complete 6 more independently. Pictures of 10-rods make the connection between sets of 10 and the corresponding...
+
Worksheet
Curated OER

Mental Math: Breaking Apart to Add

For Students 1st - 2nd
Develop mental math addition skills by breaking apart addends into 10s and extras. Worksheet has problem solving steps at the top of the page, and 8 practice exercises that lead to increasing independence using the process. 
+
Worksheet
Houghton Mifflin Harcourt

Mental Math: Subtract Tens - Homework 12.1

For Students 1st - 3rd Standards
Now that your class can add by 10s they can start subtracting by 10s. This clear, learner-friendly worksheet provides a good example (10-rods are pictured) and 7 problems to solve. Relates groups of tens to single-digit numbers, which...
+
Interactive
CK-12 Foundation

Mental Math to Multiply by Whole Number Powers of Ten: The Rule for Tens

For Students 6th - 8th Standards
Eight questions challenge scholars to use mental math while multiplying whole numbers by powers of 10. A tool with bouncing decimals demonstrates how and where the decimal moves. Question types include several multiple-choice, a...
+
Worksheet
Savvas Learning

How Many Hundreds?

For Students 2nd - 3rd Standards
Mental math skills are really important to develop. Kids practice metal computation by first adding the hundreds then the tens and ones. There are nine addition and nine subtraction problems to solve. This attractive activity is...
+
Worksheet
Curated OER

Mental Math: Add Tens Practice 10.1

For Students 1st - 2nd
In this adding tens worksheet, students solve 11 problems in which tens are added. Students may use a basic fact to help. Example: 2 tens + 1 ten.
+
Lesson Plan
Primary Junction

Adding Tens

For Teachers 1st - 4th Standards
Build on your learners' confidence in quick addition as they discover strategies to add tens to two-digit numbers. After reviewing counting by 10's, they discuss tactics to add multiples of 10 to other numbers. They visualize how to...
+
Worksheet
Curated OER

Mentally Add Larger Numbers

For Students 2nd - 4th
Using what they know about adding 10s and 100s, learners attempt to mentally solve 18 addition problems. Each problem requires them to think of the nearest 10 or 100, add them together, then add the remaining units.
+
Worksheet
Scholastic

Look for Easy Numbers for E-Z Addition

For Students 2nd - 4th Standards
All kids learn differently. For some, mental math is the best and most efficient way to add a series of numbers. After viewing a few sample problems, learners find ways to add numbers to 10 before adding them all together, and then write...
+
Worksheet
Maths Blog

Adding/Subtracting Whole Numbers in Your Head

For Students 2nd - 3rd Standards
Exercise those mental math muscles! This worksheet contains 10 addition and 10 subtraction problems which require learners to compute sums or differences in their heads. A quick review at the top of the page provides a strategy based on...
+
Worksheet
Curated OER

Number Puzzles

For Students 1st - 2nd Standards
These math puzzles are sure to get your first and second graders thinking. Nine word problems about odds and evens, as well as greater than and less than, keep learners guessing. If you're working on mental math in your class, use these...
+
Worksheet
Curated OER

More and Less

For Students 1st - 2nd
Mental mathematicians add and subtract 1, 10, and 100 from sets of numbers. Each set of one, two and three-digit numbers gives scholars a chance to practice their addition and subtraction skills. There are 62 whole numbers in all. What...
+
Worksheet
Curated OER

Mentally Add Two 2-Digit Numbers pg. 1

For Students 4th - 6th
Mental math addition is the focus of this activity. Students apply a strategy outlined in the activity to find the sums. In this activity, students find the answers for twenty problems. Answers appear at the end.
+
PPT
Curated OER

Adding in Our Heads

For Teachers 2nd - 3rd
A good presentation on adding two-digit numbers. Learners are shown how to partition the numbers before trying to add them in their heads. A frog is the featured teacher of the PowerPoint, and he leads viewers through many problems and...
+
Worksheet
Curated OER

Addition Practice #1

For Teachers 2nd - 4th Standards
Show young mathematicians that they are fully capable of mentally adding two-digit numbers. They start by solving 12 two-addend problems (all with two-digit numbers and aligned horizontally). There is no room to show work. Consider...
+
Worksheet
Curated OER

Mentally Add 3 Digit Numbers

For Students 2nd - 3rd
In this addition worksheet, students are shown how to add two 3 digit numbers in your head mentally. There are 18 problems for the students to try to work in their head.
+
Worksheet
Curated OER

Mental Arithmetic

For Students 2nd - 3rd
In this mental math worksheet, students answer 2 sets of mental math questions about writing whole numbers, place value, counting back and on in tens and addition and subtraction.
+
Worksheet
Curated OER

Mental Subtraction Methods

For Students 3rd - 6th
In this subtraction worksheet, students subtract problems using mental math methods such as tens groups, comparing problems, helping numbers, and more. Students complete 7 sets of problems.
+
Worksheet
Curated OER

Subtracting 2-Digit Numbers Mentally

For Students 3rd - 6th
In this subtraction worksheet, students subtract 2 digit numbers from each other using mental math. Students complete 12 problems and 9 comparison problems.
+
Worksheet
Curated OER

Add and Subtract to 100

For Students 1st - 3rd
These addition and subtraction problems probably aren't written the way your scholars are used to seeing them, especially since they have double-digit addends and subtrahends. This set of eight horizontal equations gives learners a...
+
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.
+
Worksheet
Curated OER

Mentally Add Larger Numbers

For Students 3rd - 6th
For this addition worksheet, students solve problems in their heads. In this problem solving worksheet, students write answers to twenty problems.
+
Worksheet
Curated OER

Sunshine Math 3

For Students 4th - 6th
For this word problems worksheet, learners read and problem solve nine  mathematical word problems involving grids, measurement, compensation and angles.
+
Worksheet
Curated OER

Look for Easy Numbers for E-Z Addition

For Students 2nd
In this mental math worksheet, 2nd graders focus on using multiples of ten to make addition problems easier to solve. They look for numbers that add to 10, 20, 30, or other multiples of 10. They write about how finding the multiples of...