Savvas Learning
How Many Hundreds?
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 worksheet is...
Maths Blog
Adding/Subtracting Whole Numbers in Your Head
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...
Curated OER
Mentally Add Larger Numbers
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.
Scholastic
Adding and Subtracting Ten
Developing fluency with basic addition and subtraction is fundamental to the success of all young mathematicians. This four-day lesson series begins with learners using ten-frames and hundreds charts to recognize patterns when adding and...
Curated OER
Mental Math Strategies
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.
Curated OER
Numbers Make Sense
Second graders explore number values by completing estimation problems in class. For this place value lesson, 2nd graders identify the use of decimals in numbers and how they relate to fractions or parts of a whole. Students utilize...
Alabama Learning Exchange
Alex: It's Automatic! More or Less With Ten
In this lesson, students will observe patterns with the use of a Hundreds Chart, web-based practice (IXL Hundreds Chart Practice), and by playing a game (10 More or 10 Less). The patterns noticed through the various activities will help...
Khan Academy
Khan Academy: Add 10s and 100s (No Regrouping)
Practice solving problems like 344+20 and 344+200. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.