English which is a second language for most Papua - New Guinea students is the medium of instruction in all secondary schools and may be a barrier to educational purpose. A list of words, non-technical but regarded as essential in the teaching of science, was drawn up by Victoria and Papuan - New Guinea teachers, tested, refined and reduced to 650 which met the criteria. Other tests of picture recognition, synonym recognition, sentence completion and correct sentence usage were tried, and an acceptable test list constructed.