Gender differences in the imaginative narrative and persuasive description writing of a sample of Year 5 (9- to 10-year-old) children were investigated using a standardised test and a repeat design, with the same tasks being undertaken a year later. The texts were analysed using test guidelines and genre-specific rating scales derived from the relevant literature. Differences in writing attainment were found to exist, with boys generally performing less well than girls. In the five constituents of writing assessed by the test, girls scored significantly higher in four in both years. Boys did not score significantly higher than girls in any constituent in either year. However, boys wrote significantly more in Year 6 than they had written in Year 5, and this may reflect increases in handwriting attainment. Boys' under-attainment was less pronounced in the persuasive description writing, and they scored significantly higher than girls in Year 5 in three features of this writing. Although a subgroup of the highest-attaining children contained more girls than boys, a detailed analysis did not indicate any girl-boy differences in textual effectiveness, content or language use. Some possible implications for practice and suggestions for further research are provided. (Contains 13 tables and 2 notes.)