AMNA NAWAZ: The African continent faces challenges as varied as its vast landmass, some three times the size of the United States.

But one shared challenge by all 54 countries is food security, how to feed a population of 1.2 billion people that's expected to double by 2050.

Fred de Sam Lazaro has a report on one attempt to build a foundation.

It's part of his series Agents for Change.

FRED DE SAM LAZARO: This picturesque 3,000-acre campus represents a $100 million effort to bring a piece of Nebraska to Rwanda, a land whose history and geography could not be more distant from the American Midwest.

On one small plot, a harvest of corn or maize is being brought in by students whose day is split between farm chores and a rigorous curriculum of biology and mathematics.

The Rwanda Institute for Conservation Agriculture, or RICA, was inaugurated in 2019, aiming to transform a profession that employs the vast majority of Africa's population.

For most, farming is an eternal struggle to earn a living or respect.

And you will never find a young person a poster or flier about agriculture, says student Joel Ishimwe.

JOEL ISHIMWE, Student: You only find old women who are from the rural areas.

You can't find some cool guys on those posters.

(CROSSTALK) FRED DE SAM LAZARO: ... find cool guys on those posters?

RICA students like this group are arguably cool, academic high achievers, among 84 chosen each year from more than 3,000 applicants.

Many come from urban and middle-class families that climb the socioeconomic ladder, leaving behind the agriculture traditions of their grandparents.

KEVIN ARAHIRWA INEZA, Student: When you come from a family of engineers, lawyers, to tell them that you're joining agriculture, they think you're crazy.

FIONA IRIZA, Student: Most of them are like, oh, you were supposed to study medicine.

FRED DE SAM LAZARO: Before coming here, how many of you had ever milked a cow?

JOEL ISHIMWE: I tried.

FRED DE SAM LAZARO: And did you get any milk?

JOEL ISHIMWE: A little.

(LAUGHTER) FRED DE SAM LAZARO: When they graduate, they will be expected to know not only how to milk cows or raise poultry, but to think innovatively about how to make agriculture more and sustainably productive.

The curriculum for their bachelor's degrees was designed in partnership with the University of Nebraska, with the wherewithal of one man from that state's most famous family, one who's no stranger to Africa.

HOWARD BUFFETT, Philanthropist: I have been to every country on the continent, as a matter of fact, and we have worked in about 44 countries.

FRED DE SAM LAZARO: Howard Buffett is the 69-year-old son of billionaire investor Warren Buffett, who is gifting much of his fortune to his children's charitable foundations.

Howard's has focused substantially on food security.

HOWARD BUFFETT: In all the places we have worked where we have seen really bad conflict, I can tell you that one denominator is, people are not getting the food they need to get.

FRED DE SAM LAZARO: In addition to unsettled conflict and weather, he says the continent has few temperate zones ideal for staple crops, and systems to transport, store and market food are also inadequate.

Rwanda, with relative political stability, was a good place to start building a system, he says, but daunting nonetheless.

HOWARD BUFFETT: Almost the entire country is made up of small holder farmers.

And if you look at the types of slopes farming on, if we can get it right in Rwanda, we can get it right anywhere.

FRED DE SAM LAZARO: Rwanda has a landmass about the size of New Hampshire, but with 10 times the population, about 13 million people.

And despite progress that's been made at slowing the growth rate, the population here is expected to double by 2050.

MAGNIFIQUE NZARAMBA, Rwanda Institute for Conservation Agriculture: It's not all our students are going to become job seekers.

They have to be job creators.

That's really our end goal.

FRED DE SAM LAZARO: Magnifique Nzaramba, who studied at Texas A&M, is a deputy vice chancellor at RICA.

So our target is to try and teach them entrepreneurial skills, business skills, but also sufficient technical skills to implement it themselves or to go work for somebody to make sure that they have -- they add value to wherever they seek employment.

FIONA IRIZA: So I want to be able to provide safe food.

FRED DE SAM LAZARO: Safe food comes with careful processing, says senior Fiona Iriza, who hopes someday to start her own business.

She also wants to reduce waste, finding new uses for, say, dairy byproduct.

FIONA IRIZA: Well, we're making cheese, for example.

The whey proteins that remain, they can also be used to feed -- to feed the pigs, because they're very nutritious.

FRED DE SAM LAZARO: Kevin Ineza, who hoped to be an engineer before coming to RICA, plans to employ similar skills in agriculture.

KEVIN ARAHIRWA INEZA: I hope to own a company that works on precision agriculture, where you can use sensors and other technologies, so that you can conserve the environment, the water, so that you make agriculture more productive.

FRED DE SAM LAZARO: Joel Ishimwe and Ornella Rukundo have their own ideas toward the same goal.

ORNELLA RUKUNDO, Student: How can we make more money through agricultural activities, and as well as integrating the crop and animal livestocks?

JOEL ISHIMWE: The thing that I want to do, ideally in five years, is to teach kids and introduce agriculture and farming practices to kids when they are still young.

FRED DE SAM LAZARO: RICA wants to make extension agents of its alumni, imparting knowledge they gain here to help farmers.

MAGNIFIQUE NZARAMBA: Maybe they're not using the right seed.

Maybe they don't have access to the right fertilizers.

So, really, our job is to listen to them, assess what is right, and then help them improve on what isn't right.

FRED DE SAM LAZARO: It's exactly the model of universities like Nebraska or Minnesota, whose agricultural researchers provide extension services to farmers, as Howard Buffett explained to RICA's first graduating class last year.

HOWARD BUFFETT: Every country in Africa needs its own version, its own version of a land grant university.

Very importantly, it would be informed by and designed for local needs, local research and local extension.

That's what the land grant university in America was built on.

FRED DE SAM LAZARO: Unlike America, where farms have gotten larger and farmers fewer in number, he says Rwanda's priority is to sustain small rural farms, which have struggled in many developing nations, driving tens of millions of people into overcrowded cities.

And the focus at RICA is on conservation agriculture, planting fields without tilling, the widespread practice, especially in the U.S., that erodes and depletes the soil of nutrients.

It requires more and more fertilizer, is polluting and, Buffett says, unsustainable.

HOWARD BUFFETT: What's the most important thing I have?

It's not my tractor, it's not my drill, it's not my combine.

It's the soil.

When you can keep that soil in place, you can increase your production, you can maintain your production, and you can keep your water clean.

And conservation agriculture is a huge contributor to the solution to several problems.

It's not just about, how do we help farmers in Rwanda farm better.

It's about, what does it mean to farm better?

They're all split into eight acres.

FRED DE SAM LAZARO: On his own farms in South Africa, in Nebraska, and here in Illinois, he says, it's meant both his soil and his bottom line remain solidly black.

For the "PBS NewsHour," I'm Fred de Sam Lazaro in Decatur, Illinois.

AMNA NAWAZ: Fred's reporting is a partnership with the Under-Told Stories Project at the University of St. Thomas in Minnesota.