In Chicago’s public high schools, many teens get their first formal taste of financial literacy training thanks to a mentoring program called Moneythink. Founded by students from the University of Chicago Booth School of Business, the volunteer-run program teaches strategies like how to budget, save, and build credit. It’s an innovative model that has scaled rapidly. To further cement their teachings outside the classroom—where real-life financial decisions are made—Moneythink partnered with IDEO.org and CauseLabs to develop a mobile app to put tools in students’ hands when they’re making spending decisions for themselves.

Working closely with the high school students, IDEO.org and CauseLabs created an interactive, social mobile app that encourages participants to track and share their financial behaviors in an unintimidating, peer-to-peer context. An Android version of the app is currently live in the Google Play store and Moneythink has recently completed a pilot with over 100 students in high schools on Chicago’s South and West sides. Learnings from the pilot are now being assessed, and the app’s creators are preparing to develop an iOS option in addition to the existing Android version. The full app experience will launch in fall 2014 for both operating systems, with the goal of reaching a wider circle of schools and organizations.

Over the course of six weeks, the IDEO.org team made two trips into the field to observe the Moneythink mentoring program in context, and to better understand the students’ experiences in school and at home. Interviews focused on how students use their mobile phones, what apps they like, and what they gain from heavy use of social media. “We found there was a great energy around young people sharing and getting feedback and affirmation about themselves,” observed John Won, the team’s project lead. The team witnessed the popularity of apps like Snapchat, and the ubiquity of selfies as a primary mode of sharing. “We wanted to capture the fun and the currency of being a young person, socializing with friends.”

One of the team’s main insights in this phase was that young people do not have regular sources of income, so it’s hard to follow traditional financial practices, like setting a monthly budget. They tend to receive money around holidays and on their birthdays, and then plan their purchases around those inflows. The IDEO.org team also observed that spending goals were often motivated by the desire for peer affirmation; a kid might save $200 to buy a pair of sneakers that would draw approval from friends. “If that’s normal,” Won reflects, “how do we stop labeling the sneakers as reckless spending, but rather find tools that are better suited to take advantage of these spending patterns?”

Initially, the team envisioned an app that would merge a mint.com model with game dynamics, leveraging the “gamification” trend in technology for youth. One idea arose from the possibility of encouraging students to use eBay or Craigslist to sell items they weren’t using. Another revolved around celebrating instances when they resisted the temptation to spend.

Based on early interviews, however, the designers found that without a social element, the students weren’t particularly engaged. At this stage, the team created a more flexible platform where they could issue interactive financial challenges. Using an Instagram-style format, the first challenge invited students to post a photo at the moment of a purchasing decision, then tag it “spend” or “save.” Other students could then like and comment on the photos, creating a positive feedback dynamic that spurred continued engagement.

As part of the project timeline, the IDEO.org team released live prototypes of the app in several Chicago high schools, using two different challenges to evaluate user engagement. One challenge, the “Business Selfie,” was geared toward helping students dress appropriately for interviews. Thought the classroom version of this exercise would have involved looking at photos and talking about etiquette, the app enabled the experience to be interactive, personal, and fun. Students went into their own closets, selected an outfit, and shared it with friends. “The challenge let them apply theory to action,” explains Won, “This is a core element of the app design: shifting from in-classroom to in-context, from in-theory to applied, from once a week to real-time, from mentor to peer.”