Summit delegates prepared the Canberra Youth Ag-Declaration, which will go to the United Nations committee on world food security this month.
Food security is "our generation's problem", Ms Crofoot said.
"Those extra two billion people (predicted world population increase by 2050), they're going to be our generation's kids ...
"So we need to be involved in those solutions."
The conference had a field trip to a woolshed but was otherwise focused on discussion, debate and actions that they could take once they returned home.
"There were a lot of very good speakers to come in and get us inspired, then we split into break-up groups," Ms Crofoot said.
Conference organisers had come up with 15 themes compiled from entry essays, and discussion and voting centred on selecting the top five topics.
"Then once we had the top five we talked about them some more and came up with solutions."
Ms Crofoot was inspired to share ideas with "such a passionate and intelligent group" of young people, who have kept in touch since with a dedicated online forum and other social media.
"That network of people going forward is going to be so valuable to all of us," she said.
"It was amazing that even one member was under 25 let alone all of them, with the things they'd done and what they'd achieved already in their lives."
Meeting and talking informally was a huge part of the conference and went on "into the wee hours", she said.
"With about 150 really incredible people and wanting to meet them all, and when we only had so much time over morning teas and meals, that time between 11pm and 3am was very useful."
Being one of the older delegates highlighted the changing world of communication for her.
"There were so many selfies and so much social media ... the way we engage in two years' time with young people will have changed so much, let alone 10."
She learned about some of the issues of African nations, places where there was real social conflict because of food insecurity, and "totally different political systems".
"It's a bit tough to talk about food security in New Zealand, when we export 90 per cent of what we produce ... New Zealand doesn't have a food security issue."
Ms Crofoot had some "interesting debates" with delegates about issues of free trade - a specialty of hers.
"Trade was one of my solutions, free and open trade allowing people who produce goods efficiently to export it to people who can't."
That included "debates with the Canadians about why they need to unprotect their dairy industry", and talk with Japanese representatives about whether the nation should try to be self-sufficient in beef.
Discussion also included, to a limited extent, the Trans Pacific Partnership (TPP) which Ms Crofoot is a supporter of, in part because of the benefits to the industry she works in - sheep and beef.
Delegates selected their highest priorities as education, communication, sustainable consumption, innovation and personal leadership.
Each of the representatives came away with "three little things" to do once they returned home.
Ms Crofoot said from online updates she saw they were making good progress, and was hoping for a "snowball effect" of change.
