A lot of concern has been raised by the KNEC and the general public over perennial poor results in mathematics. This book examines the extent to which the language of mathematics may be a contributing factor to the poor results in Kenyan primary schools. The author has analyzed how meanings of mathematical terms and related concepts are understood and / or confused by learners for whom English is a second language and whether this is a contributing factor to the dismal results in the subject. Apart from observing that students have difficulties in using mathematical terms and their related concepts, she also recommends that mathematics teachers and mathematics textbook authors need to be aware of this source of difficulty in the teaching and learning of the subject. The author has also suggested possible ways of teaching these terms so as to generate more meaning to the learners. This book is relevant to mathematics teachers, mathematics textbook authors, teacher trainers and curriculum planners in Kenya and elsewhere.