Absolute Value and Stocks
Lesson 9 of 17
Objective: SWBAT: • Define stock market and shares • Define and find absolute value • Compare absolute values
See my Do Now in my Strategy folder that explains my beginning of class routines.
Often, I create do nows that have problems that connect to the task that students will be working on that day. Today I want students to apply what they know about opposites to finding the opposite of an opposite.
I ask for a volunteer to share out his/her thinking and answer for each question. For problem 3a, I ask students to share out what they think the value is. I want students to recognize that the opposite of negative 15 would be positive 15. I tell students that we work from the inside of the parentheses to the outside. I ask for a student to apply this logic to figure out the value of 3b. Students will apply this knowledge with the absolute value symbols later in the lesson.
Students fill out notes as they watch the video. Tim speaks very quickly, so I pause the video frequently so students can record what they have heard.
At the end, I ask students a series of questions:
- What is the stock market?
- What is a share and how can you get one?
- What happens to the value of a share if the company makes more money than it spends?
- What happens to the value of a share if the company makes less money than it spends?
- Why would people invest in the stock market rather than just putting money into a savings account?
I want students to understand that the stock market is more risky than a savings account, but over time you can make a lot more money if you invest wisely.
Who owned Facebook?
I ask students to raise their hands if they’ve seen the movie, the Social Network. I explain that this circle graph shows who were Facebook shareholders before the company started public buying and selling shares on the stock market. Once Facebook went public, any of the investors were able to buy and sell their shares on the stock market. With Facebook on the stock market, other people were able to buy and sell shares of the company.
Absolute Value Notes
I read the notes and students fill in the blanks in their notes. I want students to think about absolute value as the distance of a number from zero. If students think about it as a distance, than they understand why the absolute value of a number will always be positive. We go through the examples on the page together.
Absolute Value Practice
Students work on problems 1-8 independently for a couple minutes. Once most students are finished, we come together as a class. I ask, “What is the absolute value of negative 4? What does -|-4| represent? If students are stuck, I refer back to the do now problems. I tell students that, like parentheses, we find the absolute value first and then deal with signs outside. I want students to recognize that -|-4| represents the opposite of the absolute value of negative 4.
I have students work on problems 9-12 for the last few minutes. We come back together and I ask for student volunteers to come to the document camera to show and explain their work for problems 10 and 12. I ask students if they agree and disagree with their classmates and why. Students are engaging in MP3: Construct viable arguments and critique the reasoning of others.
I am interested to see what students think about problem 12. How do students interpret “changed the most” and “changed the least”. A common mistake is that students think that the company that changed the most has to be a positive change and/or the company that changed the least has to be a negative number. I explain that in order to know which company’s stock price changed the most we need to think about change as distance. If we take the absolute value of each of the changes, we will see which stock price changed the most and which one changed the least.
- Before this lesson you need to decide which stocks you want your students to choose from in the “Company Guide” and fill it in with the most current data.
- I have found that Google Finance and Wall Street Survivor are helpful websites to obtain and track this information.
I tell students that for the next few days they are going to be “investing” money by buying shares of companies and then tracking those investments. I read through the to do list for students for the rest of today’s lesson. I pass out “Company Guides” and “Unit 3 Tracking Your Investments” packets to each student. I also give students calculators so they can quickly calculate the costs of shares and their leftover money.
As students work, I walk around and monitor student progress. Common mistakes are investing too much/too little money, making calculation errors, or not following the directions in the packet. I give students a 10 minute and 5 minute warning. In order to track their stocks they must have Part 1 completed. If it is not completed I have them come after school or assign it as extra homework.
Closure and Ticket to Go
For Closure I ask students, “Why do people take the risk of buying shares in companies?” Students participate in a Think Pair Share. I call on a few students to share out their ideas with group. I want to ensure that students understand that investing in the stock market involves risk, but if done well it can lead to higher returns than putting money in a savings account.