Ratio errors confuse a dodgeball coach as two teams face off in an epic tournament. See how mathematical techniques such as tables, graphs, measurements and equations help to find the missing part of a proportion.

True love has the right ratio. In this humorous animation, the number of words spoken by each partner predicts whether a date goes well or horribly. What do you do when someone asks if you listen to country music backwards, but won't let you get a word in edgewise?

Game Over Gopher is an exciting tower defense game that guides students in plotting coordinate pairs, differentiating negative coordinates from positive coordinates, and identifying the four quadrants. Hungry space gophers are marching towards a prize carrot, and to defend it players place tools around the coordinate grid to “feed” gophers and make them lose interest. Ruby mines (which must be placed at designated x, y coordinates) yield currency that players spend to strategically place carrot launchers, garlic rays, corn silos, and beet traps – gopher feeding tools. To introduce students to the coordinate grid, Game Over Gopher introduces new skills via interactive tutorials and uses consistent visual clues (e.g., x red, y blue) to guide players in plotting coordinates. This means it’s not necessary to teach students coordinate plotting ahead of time. As the levels progress, the number of tools available increases, the level of math vocabulary increases, the scale of the grid changes, and players are asked to expand their mastery of the grid by reflecting points across axes. The game lowers intimidation about the coordinate grid, helps students understand how positive and negative numbers reflect each other across the axes, and helps students get comfortable with the four quadrants.

"Shadows are corrupting the land. Restore the balance of nature by exploring place value. Gate guides students in: lowering intimidation about large numbers and
decimals, understanding the meaning of place value, and realizing that the same mathematical concepts that apply to the ""easy"" integers apply to every order of magnitude."

In Monster School Bus, students play a newly hired bus driver with a certain number of seats on the bus. The mission: to pick up each neighborhood’s little monsters and bring them to school – without dividing up groups (monsters don’t like that).
In early levels, each little monster takes up one seat and players combine integers to add up to 10. Each new neighborhood exposes learners to a more complex set of numbers, including decimals and fractions. The design of characters and locations gives the game an edgy look, and provides a more mature atmosphere to a game covering fairly juvenile content (e.g., buildings transform into punk Monster Buildings as a reward for picking up kids). This is important: though students learn this concept of number chunking in earlier grades, they often fail to understand it conceptually. Therefore, this content could turn off older students if they feel the game is “below them.” The edgy character design helps make the content feel more age-appropriate, and the graphical details impact gameplay and motivate players to visualize numbers as sets and quantities and think harder about relationships among numbers and number systems.

Whole numbers are no better than any others! Practice plotting values on the number line as a passionate activist rises up and demands equity for all numbers, including fractions and decimals.

Two besotted rulers must embrace proportional units in order to unite their lands. It takes mathematical reasoning to identify the problem, and solution, when engineers from Queentopia and Kingopolis build a bridge to meet in the middle of the river.

Navigate the number line while diving amidst shipwrecks and sunken ruins. Will you find a pearl, or an old boot? Watch out for the electric eel! Pearl Diver teaches properties of numbers, how to plot numbers, how to visualize quantity on the number line, how to order numbers, and how to use the number line as a visual model for mathematical operations.

Ratey pops up when you least expect him. And he can't resist pointing out the rates and "purrportions" in daily life. It turns out that everyday decisions rely on mathematical reasoning about rates.

The battle is on in this game where you build your own potions! Check your ratios to win this mixture mix-off. Ratio Rumble guides students in: identifying ratios when used in a variety of contextual situations; providing visual representations of ratios; solving common problems or communicating by using rate, particularly unit rates; and explaining why ratios and rates naturally relate to fractions and decimals.

The evil Scaleo has escaped from prison and is transforming the length, width, and height of objects until they become useless – or dangerous.
Who can put things right? Superheroine Scale Ella uses the power of scale factor to foil the villain.

The concept of water activity is important to food preservation. When water activity is less than 0.6, almost all microbes, including bacteria, molds, and yeasts, stop growing. Vegetables are usually dried even further, to water activity of 0.3 or 0.2, for quality and storage. Virtual Labs – Controlling Water Activity in Food explores a traditional method of preserving corn by drying. In this virtual laboratory, learners test water activity levels of dried corn and explore how they change under three different storage environments. The interactive animation guides users through the theory and practice of sampling a food product, using a water activity meter, and setting up replicates, to build familiarity with concepts and procedures used in real food science labs. Before beginning this lab, it may be useful to complete Virtual Labs – Understanding Water Activity.