Real-world math

Freshmen have signed up for credit cards offered by advanced algebra students at Downtown College Prep, writes math teacher Dan Greene on Exponential Curve. Older students calculated interest rates to design different plans, which they marketed to the younger students. The goal is to build financial literacy. Already, students are learning to ask questions and read the fine print.

Freshmen earn “lobobucks” for doing their job as students — turning in homework, preparing for class, etc. They receive a weekly account of earnings and expenses, such as renting a chair in class, or using “utilities” (worksheets and materials).

They must use their money to pay their bills. We are considering consequences – i.e., if you don’t pay rent, you have to sit on the floor.

. . . They can use their credit cards to buy extras (though they come at a steep price!) such as free dress, bathroom passes, homework passes, listening to music during tutorial, and a double lunch period. There will be credit limits to prevent out of control spending too.

Detentions increase interest rates.

Each Friday, my students will get a log of purchases made by the freshmen, and any payments that have been made. They will take into account any rate hikes, and will then generate a new balance and create a bill, which will be presented to the freshman on the following Monday along with their income and expenses

Freshmen who stay within their budget will get a prize at the end of the unit. Advanced algebra students are competing to see who can make the most profit by encouraging frosh to borrow more.

About 90 percent of DCP students are Mexican-American. Some are growing up with undocumented parents who don’t have a bank account, much less a credit card.

You can read more about how Downtown College Prep prepares students for college in my book, Our School.

About Joanne


  1. Speaking of math at DCP, any idea why does DCP requires 9th graders who scored proficient and/or advanced on the Algebra portion of the California Standards Test to retake Algebra?

  2. I’m not aware that they do. Dan Greene at DCP would know about that.

  3. I have students who, when they create their first amortization table, are shocked to discover that only part of that monthly payment goes to paying off the principle.

  4. They should consider entering the book contest run by ING direct right now. There’s a prize for the best kids book written by a 13-20 year old that encourages savings and good financial habits. More info at > learn more > about us > kids. Or you can go to They’ve got lesson plans and grants for K-8 teachers. Pretty cool stuff.