One way that writers of all kinds begin a piece of writing is by creating a contrast between what has happened in the past and what is happening now. When writers do this, they aren’t trying to write about history, but rather they are beginning by creating context for the ideas they are about to reveal. This little history-corner-moment provides a dynamic beginning in any content area -- from art to economics to ecology!

This short video and interactive assessment activity is designed to teach fifth graders about adding and subtracting mixed numbers - word problems.

In this lesson students will learn how to add decimals to the hundredths place.   Image by Tiffany Hale

Pressbooks is an accessible, open-source platform used to create and adapt openly licensed textbooks, courseware and academic content. The Pressbooks Directory is an incredible repository of 2000 Open Educational Materials and textbooks & course. This tutorial shows how to add Book Information and Metadata in your Pressbooks content to optimize your book's reach and search.

Open Middle provides math problems that have a closed beginning, a closed end, and an open middle. This means that there are multiple ways to approach and ultimately solve the problems. Open middle problems generally require a higher Depth of Knowledge than most problems that assess procedural and conceptual understanding.

Open Middle provides math problems that have a closed beginning, a closed end, and an open middle. This means that there are multiple ways to approach and ultimately solve the problems. Open middle problems generally require a higher Depth of Knowledge than most problems that assess procedural and conceptual understanding.

This is a 7th Grade Math Lesson on Adding & Subtracting Positive & Negative Integers. It is designed to be a 45-50 minute face-to-face lesson, however, some materials could be adapted for an online modality. Includes materials, and interactive activities for students to participate in. 

The focus of the Adding Up to Four Two-Digit Numbers intervention is adding two-digit numbers with base ten blocks.There are four phases to this intervention. Phases 1 to 3 focus on adding 2 two-digit numbers and progress from no regrouping to regrouping in both the ones and tens. Phase 4 focuses on adding 3 or 4 two-digit numbers.

Open Middle provides math problems that have a closed beginning, a closed end, and an open middle. This means that there are multiple ways to approach and ultimately solve the problems. Open middle problems generally require a higher Depth of Knowledge than most problems that assess procedural and conceptual understanding.

Have several sets of 5 interlocking cubes, legos, or blocks with 2 different colors.  Talk about how you are holding 5 objects, but you can take them apart by color as you count the amounts in each section.  For example, 1 red block and 4 yellow blocks.  When they have all been taken apart, you can put them back together.  Help your child(ren) discover how two different colored objects can be put together to make 5.  

To add the vectors (x₁,y₁) and (x₂,y₂), we add the corresponding components from each vector: (x₁+x₂,y₁+y₂). Here's a concrete example: the sum of (2,4) and (1,5) is (2+1,4+5), which is (3,9). There's also a nice graphical way to add vectors, and the two ways will always result in the same vector.​​

The purpose of this task is to study some patterns in a small addition table. Each pattern identified persists for a larger table and if more time is available for this activity students should be encouraged to explore these patterns in larger tables.

This is a lesson on addition with regrouping to help students master this skill. The students will use base ten blocks and play a game by drawing cards and adding that many cubes to their base ten blocks.  The student that reaches 100 first will win.

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important aspects of the task and its potential use.

This lesson plan is designed to provide students with the opportunity to participate in engaging activities to review previously learned strategies for adding 3-digit numbers within 1,000, as well as practice in explaining their thinking as they solve addition problems.  

This microcredential represents a teacher’s ability to understand and respond to progressions related to addition and subtraction with rational numbers, including conceptualizations, properties, strategies, and representations, by planning and implementing instruction based on the Standards for Mathematical Practice and Effective Mathematics Teaching Practices. It includes selecting, using, and adapting mathematics curricula and teaching materials, including the integration of mathematical tools and technology, as well as using and analyzing formative and summative assessments to determine where students are in learning addition and subtraction with rational numbers. This is the fifth of seven microcredentials in the Elementary Mathematics Endorsement: Rational Numbers and Proportional Reasoning. These microcredentials can be earned in any order.

As emissions of heat-trapping bases accumulate in our atmosphere, Earth's polar regions are warming more quickly than at lower latitudes. The rapid environmental changes that result from this warming can have a significant impact on the physical and mental health of rural Alaskans: unpredictable weather and changes in the seasons have made harvesting food more difficult, hazardous, and stressful. The risk of physical injury has also increased, as poor ice, extreme weather, and coastal erosion bring new travel hazards. Increasingly difficult harvest conditions for fish, shellfish, berries, caribou, and sea mammals have also increased concerns about food security. Additionally, declines in snow pack, the threat of drought, changes in lake and river conditions, and damage and disruptions to community water systems have prompted concerns of water security. The climate-related challenge faced by Alaska’s tribal health system is to recognize new health stressors and community vulnerabilities, and then find healthy adaptation strategies in an increasingly uncertain future.