CEMASTEA is the successor of the INSET Unit which was located at the former Kenya Science Teachers College (KSTC) that implemented the Strengthening of Mathematics and Science in Secondary Education (SMASSE, 1998-2003) project through In-Service Education and Training (INSET) for teachers. SMASSE project whose overall goal was, “to upgrade the capability of young Kenyans in Mathematics and Science” was conceptualized based on a history of poor performance in mathematics and science in Kenya Certificate of Secondary Education (KCSE). The project was piloted in nine districts in 1999, expanded to 15 districts in the year 2000 and later extended nationally in the year 2004.

CEMASTEA continued to implement SMASSE programmes for secondary school teachers until 2008, when the programmes were extended to primary schools. As a result, SMASSE was changed to strengthening of Mathematics and Science Education (SMASE) to accommodate both primary and secondary school activities. The secondary and primary teacher capacity development programmes are funded by MOEST and implemented by CEMASTEA. The centre is also the secretariat of the Strengthening of Mathematics and Science Education in Africa (SMASE-Africa) Association which is a continental organization with membership from 26 African countries. SMASE-Africa was born in 2001 based on recognition that challenges in the teaching and learning of mathematics and science cuts across curricula in the African continent.