Abstract
In 1983 two pilot schools in Tunis began teaching sciences and mathematics, one through French, the other through English, but based on the French curriculum and textbooks. The content and language of science was assumed to be similar: only the host language changed. In the pilot schools, physics, chemistry, and biology lessons were observed, set textbooks and their translations were compared, teachers' meetings attended, and sixth year pupils were tested. The validity of the assumption that scientific language is similar in French and English was assessed, and some of the consequences explored. The work was restricted to communication through words and non-verbals such as symbols. The results show that the assumption is only fully valid for the symbols of the elements and amino acids, and the SI system of units. Scientific language is not necessarily constant between French and English. Implications are drawn for linguistics and for the teaching of English to students of science; the differences cannot be ignored, because many of them are fundamental ones.