View this tutorial to see how to take two points on the graph of a line and use them to find the slope-intercept form of the line. [4:45]

Prepared with pre-algebra or algebra 1 classes in mind, this module leads students through the process of graphing data and finding a line of best fit while exploring the characteristics of linear equations in algebraic and graphic formats. Then, these topics are connected to real-world experiences in which people use linear functions. During the module, students use these scientific concepts to solve the following hypothetical challenge: You are a new researcher in a lab, and your boss has just given you your first task to analyze a set of data. It being your first assignment, you ask an undergraduate student working in your lab to help you figure it out. She responds that you must determine what the data represents and then find an equation that models the data. You believe that you will be able to determine what the data represents on your own, but you ask for further help modeling the data. In response, she says she is not completely sure how to do it, but gives a list of equations that may fit the data. This module is built around the legacy cycle, a format that incorporates educational research feindings on how people best learn.

Investigate the effect of gravity on objects of various mass during free fall. Predict what the position-time and velocity-time graphs will look like. Compare graphs for light and heavy objects. Was Galileo Right is the last of five SmartGraphs activities designed for a typical physical science unit of study on the motion of objects.

Students use inclined planes as they recreate the difficult task of raising a monolith of rock to build a pyramid. They compare the push and pull of different-sized blocks up an inclined plane, determine the angle of inclination, and learn the changes that happen when the angle is increased or decreased.

This MathWorld site gives Euclid's definition of a line, properties of lines, common terminology, and algebraic representations of lines and their distinctive parts in a cartesian system. The site then goes into detail of different line relations.

Explore the behavior of lines by composing equations to launch a toy airplane through a series of hoops. This interactive exercise focuses on working in the coordinate plane and deepening the understanding of how slope and y-intercept effect the appearance of linear equations.