The First International Olympiad on Astronomy and Astrophysics (IOAA) was held in Thailand in 2007 and two students from Dharmaraja College were selected to represent the national team in the above Competition. They were Chamitha Ratnayake and Yasith Mathangasinghe. Chamitha Ratnayake was able to win a prestigious Diploma in Astronomy and Astrophysics. The second IOAA was held in Indonesia in 2008 and Yasith Mathangasinghe represented the national team. He was able to win a prestigious Diploma in Astronomy and Astrophysics. The third IOAA was held in Iran in 2009 and three Rajans namely, Yasith Mathangasinghe, Shyaminda Basnayake and Danula Godagama were selected to the national team. Yasith Mathangasinghe was able to win a special award for the most creative solutions. It was the first time that a Sri Lankan astronomer has been awarded with a special award in IOAA competition. So far Rajans have successfully performed in IOAA competitions with successful participation challenging all other schools in Sri Lanka.