The TDSB is the largest school authority in Canada. It is responsible for more than 550 schools and 270,000 students. Fewer than 50 percent of these students speak English as their mother tongue, about 30 percent were born outside Canada and 10 percent have been living in Canada for three years or less. Despite this extraordinary challenge, TDSB students demonstrate above-average school attainment. Second-generation children of immigrant origin, who were born in Canada, perform on par with their peers on average.