## Lesson Sequence on Functions
*August 28, 2016*

*Posted by Edward Deleon in : algebra, graphing calculators , add a comment*

We have produced a series of online lessons on the topic of functions. As a group, these lessons address the following Common Core standards:

CCSS.MATH.CONTENT.8.F.A.1

CCSS.MATH.CONTENT.8.F.A.2

CCSS.MATH.CONTENT.8.F.A.3

CCSS.MATH.CONTENT.HSF.IF.A.1

CCSS.MATH.CONTENT.HSF.IF.A.2

CCSS.MATH.CONTENT.HSF.IF.A.3

We also have a teacher’s guide for this lesson sequence:

OER Resource: Teacher’s Guide for Functions Lesson Sequence

Here are the lessons:

OER Resource: What Is a Function?

OER Resource: What Are the Domain and Range?

OER Resource: What Is Function Notation?

OER Resource: What Does It Mean to Evaluate a Function?

OER Resource: Sequences and Functions

And here are some new lessons recently added:

OER Resource: Linear Function Models

OER Resource: Quadratic Function Models

OER Resource: Exponential Function Models

These lessons include instructional videos, as well as hands-on math through the use of an embedded Desmos graphing calculator.

Simply click on the links above and go directly to the lesson modules. You can also copy and paste these lesson URLs and include them in your assignments. Students do not need to log into anything. These free resources can be used any time and on any device.

## Math in the News: The Decreasing Price of Gasoline
*December 7, 2014*

*Posted by Edward Deleon in : algebra, graphing calculators, math, media , add a comment*

In the current issue of Math in the News we look at data around the price of gasoline and oil production. We analyze graphs and look for functional relationships among the data sets. This is a great opportunity to bring a timely, real-world connection into your classroom.

This slide show includes an embedded GoogleDoc with all the data, which you can then copy and paste into a spreadsheet or graphing calculator to create your own graphs.

## Real World Applications of Math
*February 25, 2014*

*Posted by Edward Deleon in : algebra, graphing calculators, math, media , add a comment*

**Why Problem Solving Matters**

Until students can demonstrate the ability to apply the math skills they have learned, they are merely memorizing and reciting algorithms. Students may be able to complete a worksheet of skills-based problems, yet be completely stumped by applications of those skills. Relying on textbooks to be the main source of real-world applications of math can also prove frustrating for student and teacher alike.

Problem solving is not a textbook activity, nor should it be limited to the contrived word problems that characterize so much of what is called problem solving. An effective strategy for getting students more engaged in math is to have them gather data, organize it, analyze it, and draw their own conclusions about it. There are endless sources of real-world data. In this blog posting we provide a case study.

**Case Study: Movie Data**

**Background**

Gathering data related to movies is a way to get students motivated about a subject that is part of their world. The-numbers.com has tons of data on movies. You should bookmark this site, since it is the source of endless data that can be used for exploration. Before starting an activity, here is how to gather data from the site and use it in a spreadsheet.

Suppose you want to gather the box office data for the movie *Gravity*.

1. Go to the site: The-numbers.com.

2. Search for the movie.

3. At the search results select the item that includes the box office data.

4. You’ll see the following tabs. Click on Box Office.

5. You’ll see a graph and, if you scroll down, daily and weekly box office data for that movie.

6. Suppose you want to capture the weekend box office data. Scroll down and highlight the entire data table. Copy it to the clipboard.

7. Open a spreadsheet and paste the data in the spreadsheet.

Once you have the data in a spreadsheet, you can begin manipulating it.

## Problem Solving Assignment

Once you have shown students how to access the site and how to copy and paste data, they can begin their assignment. (Alternatively, you could gather the data for the students.) Here is the problem solving scenario:

Gather box office data for a movie that premiered at least three months ago. Gather at least 12 weekends worth of box office data in a spreadsheet. Create a line graph. Describe the shape of the graph and what it says about how the movie did.

Repeat this with at least two other movies. What do you notice about the line graphs you constructed? What conclusion can you make that would apply to all movies?

Students should put together a report that shows spreadsheet data, graphs, and an analysis of their results. Here is a sample project. We’ll be using the data we gathered for *Gravity.*

From the data gathered, highlight two columns (Date and Gross receipts). You could also copy and paste those columns into a new spreadsheet.

Create a line graph using your spreadsheet (the sample shown was done with Microsoft Excel).

The graph clearly shows that the first few weekends after *Gravity* premiered account for the vast majority of its potential revenue.

Now let’s look at two other movies: *Despicable Me 2* and *Avengers*. These graphs summarize the results.

All the graphs (and your students would provide data for other movies) show that a movie’s revenue is almost entirely dependent on its first two or three weeks. After that, the revenue drops off significantly.

A student who does this activity and comes up with similar conclusions has shown some problem solving prowess. Gathering the data, analyzing it, and drawing conclusions about it are the kinds of problem solving skills that are important. Simply constructing a line graph from given data is a far cry from the kind of analysis that can, and should, be done.

This activity also has some clear extension possibilities:

- Describe how these data graphs are examples of decreasing functions.
- Find a nonlinear regression model for a data set using a graphing calculator. Test the equation with other data sets.
- Investigate the graphs of Date-vs.-Cumulative Gross (column G of the spreadsheet). Describe any patterns you see.
- Look at the Percent Change (column D of the spreadsheet) in the data. Develop a geometric series that models the data.
- Research an upcoming movie and try to develop a predictive model of how it will do over a three-month period. What information do you need?

## Conclusion

This activity includes a number of mathematical skills:

- Gathering data
- Graphing data (line graphs)
- Analyzing graphs
- Making predictions
- Nonlinear functions, regression models (as extension activities)

These skills are combined into a rich problem solving activity, with data that is of relevance to students. This activity goes beyond using math skills in isolation and presents an interesting challenge to students, but one well within their abilities, especially if done as a group activity.

## Math in the News: Issue 91
*February 14, 2014*

*Posted by Edward Deleon in : algebra, graphing calculators, math, media , add a comment*

In this issue of Math in the News we look at applications of math from the Sochi Olympics. Specifically we look at ski jumping and develop a quadratic model based on given data.

## New TI-Nspire Tutorials on Slope-Intercept
*January 29, 2014*

*Posted by Edward Deleon in : algebra, graphing calculators, How to use Media4Math+, math, media , add a comment*

New TI-Nspire Tutorials on Linear Functions and the Slope-Intercept Form. #MathChat http://ow.ly/t3gSh

## New TI-Nspire Tutorials on Linear Functions
*January 29, 2014*

*Posted by Edward Deleon in : algebra, graphing calculators, math, media , add a comment*

New TI-Nspire Tutorials on Linear Functions and the Slope-Intercept Form. #MathChat http://ow.ly/t3gSh

## New TI-Nspire CX Tutorial: Constructing the Tangent to a Circle
*January 24, 2014*

*Posted by Edward Deleon in : algebra, geometry, graphing calculators, How to use Media4Math+, math, media , add a comment*

New TI-Nspire CX Tutorial: Constructing the Tangent to a Curve. #MathChat http://ow.ly/sVGzK

## New TI-Nspire CX Tutorial: Constructing the Tangent to a Curve
*January 24, 2014*

*Posted by Edward Deleon in : algebra, geometry, graphing calculators, math, media , add a comment*

New TI-Nspire CX Tutorial: Constructing the Tangent to a Curve. #MathChat http://ow.ly/sVGzK

## New TI-Nspire iPad App Tutorials: Slope
*January 21, 2014*

*Posted by Edward Deleon in : algebra, geometry, graphing calculators, How to use Media4Math+, math, media , add a comment*

Do you use the TI-Nspire iPad App? We just uploaded several tutorials on the Slope Formula. #MathChat http://ow.ly/sNwR1

## Do you use the TI-Nspire iPad App?
*January 21, 2014*

*Posted by Edward Deleon in : algebra, geometry, graphing calculators, math, media , add a comment*

Do you use the TI-Nspire iPad App? We just uploaded several tutorials on the Slope Formula. #MathChat http://ow.ly/sNwR1