Otago Girls' High School pupil Lucy Matehaere, King's High School pupil Liam Hewson and Dunstan High School head girl Ella Creagh were selected for the trip by Royal Society Te Aparangi.
Lucy (17) has been a regular participant at the Otago Science and Technology Fair and has submitted many projects, including the effect of music on emotions; memory retention; and the effect of tidal variations on the salinity in Otago Harbour.
Liam (17) also has a long history of participation in extracurricular science activities.
He said his experiences as an academic prefect and Scout leader had given him an ''immense appreciation'' for the pristine landscape of New Zealand, and a desire to explore the great outdoors.
He is working towards a Gold Duke of Edinburgh Award and Scouting Queen's Award, and plans to go to university next year to study either biotechnology or analytical chemistry.
''This international science opportunity will allow me to channel and develop these three aspects, through collaborating with students, teachers and scientists and professors from around the world.''
Royal Society Te Aparangi chief executive Andrew Cleland said the trio were among about 100 across the country to apply for the trip.
About 500 of the world's leading young scientists, aged 16-21, would attend the two-week LIYSF residential event in July, which aims to give deeper insight into science for the benefit of all humankind.
He said it was a great opportunity for talented young New Zealanders to interact with experts at the top of their fields and to meet like-minded pupils from around the world.
LIYSF is held at Imperial College London and The Royal Geographical Society, and includes day visits to other leading United Kingdom research centres and universities, including Oxford and Cambridge.