The school was founded in 2000 by a group of parents who were looking for something extra in their children's education. The school started with 32 children in four classes by initially renting one floor of the present Infant department building shown here.
Because of strong parental demand over the next eight years the school grew steadily throughout each academic year and the number of classes needed correspondingly increased by an extra class every two years. This expansion eventually necessitated the use of a second building and a nearby language school was taken over at the end of 2007.
BISB was inspected during the 2007/08 academic year when it had grown to nearly four times its original size. The junior department opened in April 2008. This enabled the school to have one class for each year group from the 2008/09 year onwards as well as specialist rooms for French, Music and ICT teaching in each building.