Rosie Hassin and Shannon Graham were in the American capital to meet President Bush as symbols of reconciliation across the religious divide during the celebrations this year when, for the first time, the province's politicians were off the guest list.
They attend Ulidia college in Carrickfergus, which was formed in 1997 as part of a movement to educate young people from across the religious spectrum. It now has 500 students and is part of the Integrated Education movement which began in 1981 with the foundation of Lagan college, Belfast.
Five per cent of Ulster children and teenagers are educated in 57 establishments. The charity receives some government funding but relies heavily on money from the United States. It has raised around pound;7 million from various sources since 1998.
The Ulidia girls' schedule included a gala dinner, hosted by the American Ireland Fund, aimed at drumming up more financial support.
"We used to get called names ... but now things are easier," said Shannon, 16, who comes from a mixed religious background. "My parents brought me up to interact as much as I can with other religions." When she leaves, she plans to study make-up and hairdressing at Belfast Institute of Further Education.
Rosie, 18, from a Protestant background, and head prefect, hopes to study performing arts at Belfast university. "A survey here found that 80 per cent of people want integrated education but very few apply to get their kids to go," she said. "There's a huge step to make in this country."
Even so, some schools are over-subscribed and almost 700 would-be students were refused places this year.
"We see ourselves as part of the peace-building process," said Ulidia's deputy principal Olwen Griffith.
Employers have noticed the benefit of taking on former students who have a better awareness of the different traditions in Northern Ireland.
Denis Rooney, chairman of the Northern Ireland Institute of Directors, sits on the Integrated Education Fund's advisory committee. He said: "Anecdotal feedback about these students is positive. It's much better to come through the integrated process.
"We've been successful in working towards a neutral workplace, but those who come from segregated areas have to be conditioned. You also lose the synergy that's part of the entrepreneurial spirit - something that's very low here.
"Employers come in to do mock interviews and the word back is always that they have confidence - not only here but at other integrated schools too."