Although the teaching of children's oral language is critical to both their social development and academic success, the assessment of oral language development poses many challenges for classroom teachers. The aim of the study is to develop an approach that: (i) enables teachers to assess oral language in a reliable, valid and comparable manner and (ii) provides information to support targeted teaching of oral language. The first stage of the study applies the method of pairwise comparisons to place exemplars on a scale where locations represent the quality of oral performances. The second stage involves teachers assessing oral narrative performances against the exemplars in conjunction with performance descriptors. The findings indicate that the method provides a valid and reliable way for classroom teachers to assess oral language of students aged approximately four to nine years. The assessment provides teachers with information about students' oral story-telling ability along with information about the skills that students need to learn next.