Graphing Functions in a BYOD Classroom

Student graphing with an iPod touchGraphing functions in Algebra class is a task that has long been dominated by the use of a TI graphing calculator. But now, in a Bring Your Own Device classroom, students can work with these function graphs using an iPhone, iPod, or Android phone/tablet. Oh, and they can still use the good old graphing calculator too. Here is the lesson we had just done with several of our Algebra classes using multiple devices for graphing absolute value functions. The lesson was completed in one – 60 minute class period.

The Algebra teachers who planned the lesson, Andy Elder and Cheryl Hoffman, are the same teachers who have been using iPods in the classroom for several other activities, including QR codes and student review videos. Since our school has a BYOD policy, the students were encouraged to bring their own device to use, if they had one. The classes were told that we would also have a set of 30 school iPod Touches available for use. The students were informed that if they used their own device they would need a graphing calculator app. For the iOS users, we told them to install the free app Meta Calculator. The Android users downloaded the free app Graphing Calculator . A few students used their own Texas Instruments graphing calculator.

Student using graphing calculator app on an Android tablet.

Students using graphing calculator app on iOS and Android devices

Students had already learned about absolute value, functions, and function tables. In this lesson, students would learn how the position of an absolute value function graph would change based on a change to the equation. For example, how the position of the graph changes between the equations :

function of x equals absolute value of x

Function equation 1

function of x equals the absolute value of x minus two

function equation 2

Students were given a handout with the equations and graph grids. The first graph was created by hand, as the teacher led the class in completing the table of values, sketched the graph, and described the function line ( stating the position of the vertex in regards to the origin, direction of the line ).

Data table for equation, graph grid, description of graph

First graph done by hand

Once the graph was done by hand, the students then used their device to graph the function. We projected screenshots for the app Meta Calculator, leading the students on how to input the equation for the graph. While not every single student was using the same type of app, we found that the screenshots helped the Android users as well, since the apps were so similar.

Graphing Calculator Layout

Screenshot from Meta Calculator App

After the students were able to recreate the first graph on their device, they proceeded through the handout graphing, sketching, and describing the shape of each equation graph.

Student Graphing absolute value functions on an iPod

Graphing absolute value functions on an iPod

The students also had a section at the end where they had to record their prediction for the shape of the graph of 9 different equations and then verify the appearance with their device.

List of nine function equations to predict the shape of the graph

Analysis – use what you learned to predict these graphs

The lesson demonstrated how, in a BYOD classroom, it does not matter what the tech tool is that you use. Students had to create a graph of an equation –  it did not matter if they used a Kindle Fire, iPhone, or HTC phone to do so. The use of the tech tool was not the center of the lesson – the technology simply allowed students to focus on the concepts of absolute value, functions, and graphing.  Students could spend more time determining the cause and effect relationship between the function equation and the shape of the graph, and less time on the lower level task of constructing each graph by hand. We also observed several students experimenting by inputting their own equations – to see what would happen to the graph. This experimentation will help those students develop deeper understanding of the concepts from the lesson.  The closure for the lesson indicated a high amount of comprehension of the objectives from the class. Both Mr. Elder and Mrs. Hoffman were pleased with the results and thought it was an effective lesson .


About John Sengia

Instructional Technology Specialist for a school district in York County, PA. Former science teacher. Looking to help teachers use technology naturally with their teaching instead of trying to "add it in" .
This entry was posted in BYOD, Handheld Devices, iPad, iPod, Uncategorized and tagged , , , , , , , , . Bookmark the permalink.

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