The 14 students attended the Pheasant Wood Commemoration Service in Fromelles, France, where they laid wreaths on the graves of 13 local Diggers.

5533 Australian soldiers were killed or wounded in the conflict, often described as one of Australia's bloodiest battles.

The students also met Governor-General Quentin Bryce, Prince Charles and Camilla Parker Bowles at a private reception.

Year 11 student Jessica Blanch researched the life of Private Henry Cressy of Boolaroo, who was 22 when he died.

"I spoke to his relatives beforehand and they gave me his diary to read," she said.

"Reading his diary and going on the trip just put everything into perspective . . . why they were fighting.

"It was such an amazing experience."

The 17-day trip was part of a modern history study that also included battlefield sites in Singapore, Turkey, France and Belgium.

Jessica said the trip has inspired her to keep studying modern history for her HSC.