Addition is really about finding sums, or totals. Subtraction is about finding the difference between two numbers. Learn more about adding and subtracting without regrouping with this step-by-step, interactive video from StudyJams. A short, self-c...hecking quiz is also included with the link.[more]

This short video teaches you how to use the order of operations correctly. They use Please Excuse My Dear Aunt Sally.
Please - Parenthesis, Excuse - Exponents, My - Multiplication, Dear - Division, Aunt - Addition, and Sally - Subtraction as a mnem...onic devise.[more]

From discoveryeducation.com, produced by Discovery Education

In this computer-animated video, students are taught to add two digit numbers using regrouping. Students are also shown a strategy for adding two-digit and one-digit numbers using mental math. (03:23)

In this video, Mr. Almeida explains how to use mental strategies to add and subtract within 20 using the relationship between addition and subtraction. This is one of the strategies suggested in the Common Core State Standards for Mathematics, 1.OA.6... and 2.OA.2. This would be a great resource for teacher professional development or for direction instruction. (4:22)[more]

En este video, el profesor habla sobre varias operaciones básicas. Empieza con el valor absoluto y sigue con la suma de enteros, resta de enteros, multiplicación de enteros, y la división de enteros. El video ofrece ejemplos de cada operacion. (10:17...)[more]

In this "Fizzy's Lunch Lab" interactive, students use math to complete Corporal Cup's challenges that involve sorting, counting and measuring. Unlock her top secret recipes by counting types of fruits, completing fruit equations and measuring food sl...ices.[more]

In this video, Mr. Almeida explains how to use mental strategies to add within 20 using the "make 10" strategy. This is one of the strategies suggested in the Common Core State Standards for Mathematics, 1.OA.6 and 2.OA.2. With practice, this strateg...y can help students gain fluency when adding within 20. Eventually students will memorize these facts, which is expected by the end of grade 2. This would be a great resource for teacher professional development or for direct instruction. (5:48)[more]

• Detailed description of the three domains of numbers and operations (Operations and Algebraic Thinking; Number and Operations in Base Ten; and Numbers and Operations -- Fractions)
• Arithmetic as a rehearsal for Algebra (2mins)

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