Abstract
A method was developed for representing school pupils’ knowledge about, and associations with, six basic scientific concepts, by classifying and coding the ideas produced in a free‐writing task. This allowed for quantitative comparisons within and between groups of pupils from different language backgrounds, all of whom were learning science through the medium of English. The results imply that those differences which exist can best be attributed to general fluency in, and familiarity with, the language of instruction, rather than to factors which are specific to the learning of science. This suggests perhaps the need for a greater emphasis on tasks which specifically involve and seek to develop language use as a element in the learning of science for all learners.