TESSA (Teacher Education in Sub-Saharan Africa) aims to improve the classroom practices of primary teachers and secondary science teachers in Africa through the provision of Open Educational Resources (OERs) to support teachers in developing student-centred, participatory approaches. The TESSA OERs offer activities for teachers to try out in their classrooms with their students, together with case studies showing how other teachers have taught the topic, and linked resources to support teachers in developing their lesson plans and subject knowledge. TESSA OERs have been collaboratively written by African and international authors to address the curriculum and contexts. They are available for online and print use (http://www.tessafrica.net). Secondary Science OER are available in English and have been versioned for Zambia, Kenya, Uganda and Tanzania. There are 15 units. Science teacher educators from Africa and the UK, identified five key pedagogical themes in science learning: probing children’s understanding, making science practical, making science relevant and real, creativity and problem solving, and teaching challenging ideas. Each theme is exemplified in one topic in each of Biology, Chemistry and Physics. Teachers and teacher educators are encouraged to adapt the activities for other topics within each subject area. We welcome feedback from those who read and make use of these resources. The Creative Commons License enables users to adapt and localise the OERs further to meet local needs and contexts. Contents Module 1 Biology ● Section 1 Classification and adaptation ● Section 2 Transport ● Section 3 Respiration ● Section 4 Nutrition, conservation and ecology ● Section 5 Cells Module 2 Chemistry ● Section 1 Elements, compounds and mixtures ● Section 2 Acids, bases and salts ● Section 3 Combustion ● Section 4 Atomic structures, chemical families and the periodic table ● Section 5 States of matter Module 3 Physics ● Section 1 Properties of matter ● Section 2 Measurement ● Section 3 Pressure and heat transfer ● Section 4 Forces ● Section 5 Electricity and magnetism