This section draws on previous sections that explored how to add, subtract, multiply, and divide rational numbers in order to solve real-world problems involving rational equations. It explores how to apply these procedures in order to solve equations.

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Science learning often involves creating abstract representations and models of processes that we are unable to observe with the naked eye. Learn more about visualizing, representing, and modeling to aid struggling learners.

This comprehensive study guide highlights the main terms and formulas needed to understand graphs of rational functions. Examples are included.

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ALMA'S WAY follows 6-year-old Alma Rivera, a proud, confident Puerto Rican girl who lives in the Bronx with her family among a diverse group of close-knit friends and community members. In every episode, It aims to model self-awareness, self-advocacy, social awareness, cultural competency and responsible decision-making -- encouraging kids to generate and value their own ideas and questions. It celebrates and explores the thinking process -- Alma's "way" is to think things through. As she shares her observations and feelings and works through challenges, she speaks directly to young viewers, offering them a window into her everyday life. This Collection includes: Video (10), Media Gallery (3), Webpage (2) for Grades PreK-K, K-2 , Resources in Spanish (3).

Students will practice counting from 1-30 and having one-to-one correspondence with objects for these numbers. Also, they will practice finding patterns on a hundreds chart. This lesson includes a detailed plan, videos of students participating in a counting chain, and a printable ten frame worksheet.

In the NGSS, one of the performance expectations is for the children to develop a model to represent the shapes and kinds of land and bodies of water in an area. In the science practices, the children also must develop and use models. This lesson will help them understand that process. Video clips of the student's explaining their models are included.

Using a mathematical model, students will be able to visually see the process of how to multiply a fraction by a whole number to find its product in order to gain a deeper understanding to ultimately be able to do it on their own.

A lesson focused on subtracting mixed numbers using fraction strips and an interactive fraction pad.

Find animated diagrams that describe both eukaryotic cells and prokaryotic cells. There are models for animal, plant, and bacteria cells.

In this context-setting lesson, students will run and collect data from a simple simulation in Sprite Lab. After running the simulation multiple times, students will have an opportunity to predict how changing a variable in the simulation might impact the outcome and test that hypothesis. This lesson aligns to national Computer Science standards from CSTA.

This lesson combines skill-building around events with a mini-project where students get to build their own computer simulation in Sprite Lab. Students will study the simulation to understand how quickly a virus can spread and what can be done to slow it down. This lesson aligns to national Computer Science standards from CSTA.

In this exploratory lesson, students will train a machine learning model by classifying fish and other objects. This lesson aligns to national Computer Science standards from CSTA.

This online interactive module of 10 pages or frames integrates textual information, 3D molecular models, interactive molecular simulations, and embedded assessment items to guide students in understanding the copying of DNA base sequences from translation to transcription into proteins within each cell. The module divides the exercises in to Day 1 and Day 2 time frames. Teachers can view student assessment responses by assigning the module within a class created within the Molecular Workbench application. This Java-based module must be downloaded to each computer.

Engineers use a series of steps called the design process to solve a problem. In this resource, featuring video segments excerpted from DESIGN SQUAD, watch teams of kids work through each of the five steps of the design process: 1) identify the problem; 2) brainstorm; 3) design; 4) build, test, evaluate, and redesign; and 5) share solutions. [1:47]

Make a scale model of the Solar System and learn the REAL definition of "space." You tell it how large to make the sun (in inches or millimeters) and the page will do all of the calculations for your scale model solar system and provide other scaled data. Requires JavaScript capable browser. Links to a more detailed page that calculates sizes and distances for moons also.

The WebMuseum offers a biography of Georges Seurat (1859-1891 CE), known for his creation of the Pointillism technique of 19th century neo-impressionist painting. Content includes numerous samples of his work, as well as full descriptions of each piece.

How do animals digest food? Animal nutritionists determine feed rations for livestock, zoo animals, and pets related to their dietary needs but also their digestive systems. This unit will make a connection between soybean used as high protein feed and the types of digestive systems in animals. This unit features 3 lessons and 7 files. Lessons are aligned to NGSS.

A mathematics tutorial that allows you to interactively learn and manipulate the slope and intercepts of a line.

Discover different types of compounds such as binary covalent, binary ionic, binary acids, and oxyacids. Explore links that give information about writing names and formulas for different compounds.

This excellent high school physics tutorial from The Physics Classroom investigates motion formulas using several problem-solving strategies including diagrams, equations, and lists.