Answer: TIMSS was first administered in 1995, and operates on a four year cycle. South Africa did not participate in TIMSS 2007 as we wanted to allow time for the many educational interventions that were being implemented, to improve mathematics and science, to take effect before testing again. Countries in the Northern Hemisphere conduct the assessment between April and June of the assessment year, while countries in the Southern Hemisphere conduct the assessment in October and November of the assessment year. In both hemispheres the assessment is conducted near the end of the school year.