https://www.khanacademy.org/math/arithmetic-home/addition-subtraction/basic-add-subtract/v/basic-addition
Learn how to add numbers using circles or number lines with this video tutorial by Sal Khan. See examples, practice problems and comments from other learners.

https://www.khanacademy.org/math/arithmetic-home/addition-subtraction
Unit test. Test your understanding of with these NaN questions. Start test. In this topic, we will add and subtract whole numbers. The topic starts with 1+1=2 and goes through adding and subtracting within 1000. We will cover regrouping, borrowing, and word problems.

https://www.mathsisfun.com/numbers/addition.html
Learn what addition is, how to do it with numerals and words, and practice with examples and worksheets. Find out the addition table, tips and tricks, and other names for addition.

https://www.splashlearn.com/math-vocabulary/addition/addition
Learn what addition is, how to add numbers using different methods, and the properties of addition. Explore addition games, worksheets, and word problems on Splashlearn.

https://www.cuemath.com/numbers/addition/
Learn what is addition in maths, how to use the addition symbol (+), and how to solve addition sums with or without regrouping. Explore number line addition and practice addition problems with Cuemath.

https://en.wikipedia.org/wiki/Addition
Addition is one of the basic arithmetic operations that combines numbers or other objects. Learn about its notation, interpretations, properties and how to perform addition with different methods and systems.

https://doodlelearning.com/us/math/skills/addition/addition-in-math
Learn how to add numbers using different methods, such as number lines, fingers, and carrying. Find out the definition, examples, and formulas of addition in math.

https://www.ixl.com/math/addition
IXL offers over 200 interactive skills to practice addition for pre-K to eighth grade. You can preview, practice and track your progress on addition facts, word problems, number lines, expanded form and more.

https://www.math.net/addition
Learn what addition is, how to add numbers and objects, and the properties of addition. See the addition table with examples and related words.

https://byjus.com/maths/addition/
Learn the basic concept of addition, the symbol (+) used to perform it, and different methods to add numbers with examples. Find out the properties, addition table, and word problems on addition.

https://www.khanacademy.org/math/early-math/cc-early-math-add-sub-20
Level up on all the skills in this unit and collect up to 1,300 Mastery points! Math can be a blast! In this unit, you'll learn about adding and subtracting numbers up to 20. That might sound tricky, but you'll have all the tools to help you out. Place value blocks, ten frames, arrays, and number lines can all make solving words problems a snap.

https://www.mathsisfun.com/numbers/addition-tips-tricks.html
Learn how to make addition easier with various strategies and examples. Use counting, jumping, adding up to ten, doing the tens last, aiming for ten, compensation, doubling, and the addition table.

https://www.wikihow.com/Add
Take single-digit numbers, like 5 and 8, and try to add them together. Or, use small items, such as beans or coins, to help you visualize the problem. Next, you can start adding numerals, which includes decimals. Then, try a few techniques to help you add quickly! Adding negative numbers is a little tricky, but it gets easier with practice.

https://math.libretexts.org/Bookshelves/PreAlgebra/Fundamentals_of_Mathematics_(Burzynski_and_Ellis)/01%3A_Addition_and_Subtraction_of_Whole_Numbers/1.04%3A_Addition_of_Whole_Numbers
Learn how to add whole numbers using the plus symbol (+) and the equal symbol (=). See examples, definitions, and practice problems with carrying and regrouping.

https://www.youtube.com/watch?v=rPVdItitgIU
Learn the basics of addition and subtraction with this catchy song by Jack Hartmann. See examples of adding and subtracting numbers, words and zero with fun problems and animations.

https://www.khanacademy.org/math/arithmetic/arith-review-add-subtract
Adding multi-digit numbers: 48,029+233,930 (Opens a modal) Practice. Multi-digit addition Get 3 of 4 questions to level up! Subtracting within 1,000,000. Learn. Relate place value to standard algorithm for multi-digit subtraction (Opens a modal) Multi-digit subtraction: 389,002-76,151

https://www.math-aids.com/Addition/
These addition worksheets are great for practicing adding together two measurements of feet with fractional inches. These worksheets will use 1/2's, 1/4's, 1/8's. 1/16's and there is an option to select 1/32's and 1/64's. Decimal Numbers Addition Worksheets. Vertical Format - 2, 3, or 4 Addends.

https://www.math-drills.com/addition.php
Games help students develop mental addition skills but in a fun context. For the adding with playing cards worksheets, a Jack is counted as 11, a Queen as 12, a King as 13 and an Ace as 1. Playing math games while enjoying some social time with their friends is a great way to develop strategic thinking and math fluency in children. Adding With

https://www.calculatorsoup.com/calculators/math/long-addition-calculator.php
Add whole numbers and decimal numbers using long addition showing work. Enter numbers separated by commas or new lines and see the steps and answer for adding numbers.

https://www.khanacademy.org/math/algebra-basics/basic-alg-foundations/alg-basics-negative-numbers/v/adding-integers-with-different-signs
On a number line, 91 is 91 hops to the left of 0. 93 hops is 93 hops to the right of zero. When adding negative and positive numbers, you always want to stay close to the number 0. The difference between the numbers 91 and 93 is two. When you add +93 to -91, you can easily get to 0 by changing the 93 to a 91. -91+91 is 0.

https://dictionary.cambridge.org/dictionary/english/adding
Learn the meaning of adding as the present participle of add and as a verb meaning to put numbers or amounts together. See how to use adding in sentences and idioms with examples from the Cambridge English Corpus.

https://www.mathgames.com/addition
Adding Three or More Numbers Compatible with tablets/phones 2.66 / Add Numbers - Sums Up to 1000 Compatible with tablets/phones 2.67 / Addition Input/Output Tables with Sums Up to 1000 2.68 / Complete the Equation with Sums Up to 1000

https://www.khanacademy.org/math/arithmetic-home/addition-subtraction/add-two-dig-intro/v/adding-whole-numbers-and-applications-1
Learn how to add two-digit numbers with regrouping and carry over. Watch a video lesson, practice with interactive exercises, and check your answers.