About 30 professional football players attended a mini-camp in Florida in April. But it wasn’t to sweat it out on the field against other players. It was to learn enough about the financial industry to be able to make their money last long after they stop playing.

Tales of NFL players ending up in financial ruin have been chronicled in stories and documentaries in recent years. So the league started a camp to teach the players to be as smart about P/E ratios as they are about X’s and O’s.

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“If you take advantage of this camp, you will make a difference in someone’s life,” said Charles Way, NFL vice president of Player Engagement, in his opening remarks for the camp.

Unlike the rookie symposium, which offers incoming players tips on how to pick an investment adviser and be smart with their money, the personal finance boot camp is “for guys who have attained a second contract. It’s to help them not just set up their kids, but their grandkids,” said Way, who is 43 and played for the New York Giants between 1995 and 1999.

And it was clear in the first session that this wasn’t just basic personal finance advice.

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In the first class, “Funding an uncertain lifespan,” the instructor, Patrick Kerney, showed the following slide on a projector: “Gross margin %” equals “Sales - Cost of Sales” over “Sales.” It was one of many formulas shown in the class; this one was used to illustrate how much people pay for goods at Target TGT, +0.82% versus Louis Vuitton. Many students, engrossed, took out their cellphones to take a picture of the formula. (Speaking of name brands, fashion among the players ran the gamut, from shorts and flip-flops to smart-looking suits and everything in between.)

Kerney focused on staying ahead of inflation. “Inflation is the bear,” he said. He played in the NFL for 11 years and is now director of business development at National Fire & Casualty Investments. After retiring from the league, he got his M.B.A. at Columbia University and was the vice president of player benefits at the NFL.

Kerney also talked about the importance of what the players can control: Where they live, how much they spend, what level of goods and services they purchase, and knowing the difference between want and need.

The NFL’s second annual Personal Finance Camp ran from April 4 through April 7. Held in Fort Lauderdale, it was hosted by NFL Player Engagement, which offers various career development programs and aims to help make players’ money last and to prepare them for their post football-playing lives. The cost to attend is covered under the league’s tuition assistance plan.

And based on the attentiveness of the students, the well-rounded curriculum is making an impact with the players who attend. Joshua Martin, a 24-year-old linebacker with the Jets, is someone who has taken advantage of the camp. He attended the first one last year, and afterward changed his accountant and adviser. “I learned what questions I should be asking,” he said, while attending this year’s camp.

All the attendees posing for a picture. NFL

Forty-five people participated in the camp, including 28 players and 16 significant others — and one mom.

“We found that significant others are key influencers on a player’s life. We want the people around them to understand the decisions they make,” said Way.

Asked why he was attending the Personal Finance Camp, James-Michael Johnson, a 26-year-old linebacker on the Miami Dolphins, said he liked to take advantage of all the financial benefits the NFL has to offer — the savings benefits and the development offerings like this camp. His wife, Aleesia Sims, attended with him.

They said they attended the NFL Business Academy earlier this year, which was a five-day event. Sims said most days there were sessions from 8 a.m. to 8 p.m. Johnson said they learned about investing in franchises and real estate there, among other strategies.

The NFL put the camp together with the University of Miami’s School of Business Administration and TD Ameritrade AMTD, +0.72% .

At 8:10 a.m. on the second day, a professor from the University of Miami — Henrik Cronqvist — led a discussion on the psychology of money. He talked about theories such as loss aversion and nature versus nurture, and gave the players advice on how to improve at saving money.

He said people shouldn’t allocate much money toward individual stocks, but rather put savings on autopilot by investing in index funds. And he advised them take advantage of employer matching in savings vehicles like the 401(k).

His presentation showed that of nearly 3,000 actively managed funds in the top 25% of funds over the previous 12 months, only two funds stayed in the top 25 a year later. Cronqvist made it clear that he thought the best path for the players was to diversify, invest in index funds, and focus on low fees when investing. Not one person looked at their phone during the hour-long session. Most players and significant others took many notes. At one table, a wife was taking notes even though her husband wasn’t there.

At another, a player’s mom took notes. Her son, Antrel Rolle, a 33-year-old safety with the Chicago Bears, wasn’t able to attend. She planned to attend with him, but still came to learn on his behalf. Armelia and her son are famously close. When I asked her how often she and her husband go to his games, she said: “We haven’t missed a game since he started playing at six years old. Six years old! We travel all over.”

In terms of diversification, Cronqvist recommended equities for economic booms, bonds to insure against stock market busts, and alternative investments to ensure against inflation.

He ended by saying the famed investor Warren Buffett has advised that after he passes away, 90% his estate — billions of dollars — should be invested in a low-cost S&P 500 index fund.

At the Q&A after the professor spoke, many players asked questions, including what’s the right percent of alternative investments to put your money into, what are examples of alternative investments, and how and when do mutual funds charge fees.

Other classes included “Funding an uncertain lifespan,” “Understanding and optimizing your NFL player benefits,” “Love and Money: Crucial conversations with the people we love,” among others. And there were sessions that were closed to the media because they involved one-on-one meetings between players and session leaders.

There are almost 1,700 players in the NFL, and only about 30 attended the camp. Which helps explain why the ones who did were so attentive. They wanted to be there.

Asked why more players don’t take advantage of offerings like the personal finance camp, Tim Masthay, a punter with the Green Bay Packers, said, “For some guys, the season ends, they do their exit interviews with the coaches, and they just want to relax in the offseason.” His wife, Amanda, said some players might not want to attend something like the personal finance camp because it would feel like being at school. And she said the offseason is a time when a lot of guys get married. Still, Tim said it surprised him that more players didn’t take advantage of the 401(k) program — or other benefits the league offers.

The NFL has one of the best 401(k) programs in the country, according to Kerney. Players are automatically enrolled, and can put in up to $18,000 a year (unless they’re a rookie or on a practice squad). And the league will put in two dollars for every dollar a player puts in — up to $13,000. So a player can set aside $44,000 a year in the plan ($18,000 + $26,000).

Charles Way says only 20 players and six significant others attended the camp in 2015 (compared with the 45 total who came in 2016), and he thinks attendance will continue to rise each year as players who attend talk about what they learned with their teammates.