Introduction to Point-Slope Form

I created this Desmos activity to help students understand point-slope form of a linear equation, both how it relates to the equation for calculating the slope between two points and why it might be useful even if you're already good at slope-intercept form. It also introduces the idea of calling the change in x by the name h.

SolveMe Mobiles

The puzzles at SolveMe Mobiles are linear equations disguised as perfectly balanced mobiles. The early puzzles are simple while the later ones require solving systems of equations. The interface is elegant. Drag a beam to have the corresponding equation appear. Drag a shape that's on both sides of an equation to subtract it. Drag a common factor to divide by it. Substitute by dragging a shape that you've isolated on one side of an equation to somewhere else it appears. Create your own mobiles. Play without creating an account or create an account to save your progress and creations. (No email is required to create an account, though those over 13 may include an email for the purposes of password reset.)

Find the equation of a line

In this applet a line is randomly generated and the user enters what she thinks the equation is. Her equation is then graphed for comparison with the original. There is a scoring mechanism incorporated as well.

This is my first applet created with JSXGraph , which looks quite promising (though it does require learning Javascript.)

Particularly helpful to me in developing this were Dr. Carol Fisher's Reference on JSXGraph Commands and the convert-to-math script  in use at interactive mathematics. (The latter enables the user to enter the equation using standard calculator notation.) I also found the javascript tutorial at w3schools.com a very useful introduction to javascript.

The application uses MathJax to produce nice mathematical notation.

Vectors in the Ocean

This applet provides an introduction to the vector equation of a line in the context of a boat traveling in the ocean. You specify the position vector and the velocity vector and then watch how the boat moves and the equation changes as the time changes. (Making the ocean visible sets the mood, but turning it off makes it easier to see what's happening!)

Practice writing linear equations

This applet that I developed using Geogebra generates a line, asks the user to provide an equation and then indicates whether the submitted equation is correct.

Finding Equations of Lines in Photos

This is a set of applets I made using Geogebra. In each applet you fit linear equations, in slope-intercept form and point-slope form, to linear elements of photographs. The applets are all the same except that each uses a different photograph. I also developed a worksheet to go along with the applets, and it is included at the bottom of each applet.

Solving Linear Equations with Step-by-Step Checking

This is a very slick applet from WisWeb for providing practice solving linear equations (and showing your work!). You can use one of the 20 equations given or type in one of your own. Specify what you want to do to each side as the next step (e.g., add 4, combine like terms, distribute) and then do it. The applet will then indicate whether you have correctly carried out the operation you specified. Continue until the equation is solved.

There are a couple of other versions of this applet which have more practice problems, grouped by difficulty, but they do not include the option to enter your own equation. You can find them here and here.

Algebra vs. the Cockroaches

In this game from Hotmath.com cockroaches crawl along a line in Cartesian coordinate system and you must type in the equation of the line to get rid of them. Equations get more difficult as the rounds progress.

Larry Green's Line Graphing Applet

This is a very simple applet that will be helpful to students in the early stages of learning to graph a line in slope-intercept form. It is easy to use and provides helpful feedback. It will give students practice graphing lots of lines in a short amount of time.

Transum Software

This site has some good interactive activities appropriate for students in roughly grades 3 through 10. By clicking on the images here, you can experiment with those that I am most likely to use with my Algebra 1 class.