AAA Math
Aaa Math: Adding Two Digit Numbers Mentally
Read these two strategies for adding two-digit numbers in your head. Then try out the one you like better by playing the game. Running totals of your correct and incorrect answers as well as a percent score of your correct answers will...
AAA Math
Aaa Math: Adding Three Digit Numbers
Read through this explanation of how to add three digit numbers. Use the online game to practice this skill. The game will keep running totals of your correct and incorrect answers. It will also show you a percent score of the correct...
AAA Math
Aaa Math: Mentally Adding Two Digit Numbers
This site explains how to mentally add two-digit numbers. Gives exercises and games to practice this skill.
Illustrative Mathematics
Illustrative Mathematics: Saving Money 2
The purpose of this task is for students to relate addition and subtraction problems to money and to situations and goals related to saving money. A problem is given that will contain multiple solutions, this allows students to think...
NumberNut
Number Nut: More Than Two Addends
Develop strategies for adding more than two addends with this quick addition lesson. Examine how grouping numbers can help make adding multiple numbers easier. Then, practice your new skills using the related interactive games that are...
Teaching Treasures Publications
Teaching Treasures: Year Two Timed Mental Math (Page 3)
Increase your addition and subtraction speed using this timed interactive worksheet. With just ten problems and five minutes, this worksheet is suitable for practice or as an assessment tool. Check your answers immediately.
Lawrence Hall of Science
The Math Page: Skill in Arithmetic: The Meaning of Subtraction, and Mental Calculation
This website explains and defines basic subtraction. There are practice problems at the very end of this lesson.
Homeschool Math
Homeschool Math: Adding and Subtracting Decimals With Two Decimal Digits
This is a complete lesson with instruction, word problems, and exercises about adding and subtracting decimals with two decimal digits (hundredths).
CK-12 Foundation
Ck 12: Elem Math: Adding and Subtracting Three or More Numbers
[Free Registration/Login may be required to access all resource tools.] This is a set of practice problems where students are given word problems where they have to add or subtract 3 or more 1-digit numbers.