In mathematics, 67% of students scored at level 1 or below which indicates that they struggle to undertake very basic operations and interpretations (PEN, 2015). The OECD Programme for International Student Assessment (PISA), which focused on the performance of 15-year-olds in science in 2015, shows that Costa Rica performs well below OECD countries and at no more than the average level for Latin America (see Chapter 1). The high proportion of 15-year-old students who lack basic skills in science (46%) and do not reach the level of achievement (level 2) regarded as the minimum needed for full socio-economic participation is one of the largest among PISA participating countries and more than double the average across OECD countries (21%).