Published online by Cambridge University Press: 10 October 2018
Many studies show that it is challenging to encode morphosyntactic information while writing. Spelling plurals is especially demanding in French as these are inaudible. Even by the end of primary school, monolingual French pupils still have difficulties marking plurals of some grammatical categories. We investigate (1) how multilingual pupils learning French as a second written language deal with silent plural markers and (2) the effects of a morphosyntactic training explicitly focussing on grammatical categories and their markers, as well as visualizing the plural agreement. 228 fifth graders were quasi-randomly assigned to an intervention (n = 137) and a control group (n = 91) based on the results of a spelling pre-test. The results of the pre-test show that multilingual learners have similar spelling patterns as French monolinguals. They pluralize nouns more accurately than verbs and perform lowest on adjectives. After the pre-test, both groups were trained over six sessions of 20 minutes. The control group participated in French listening comprehension activities. The post-test shows that the intervention group significantly improved in spelling plurals compared to the control group. A greater focus on morphosyntactic structures is highly effective especially in second language contexts where children might lack broad lexical knowledge.