What is a teritary qualification?

In Australia and New Zealand, primary school teachers usually need to be qualified to teach in a range of key learning areas (KLAs) in at least three of six categories, including English, mathematics, science, social sciences, expressive arts. After qualifying in two of these (a primary and secondary qualification), then the third (tertiary) qualification must be in psychology, education, special education, a language, English as a second language (ESL), computer studies, media studies, library science to work with students with special needs.