英语写作评价是提升英语写作能力的重要手段。当前我国中学英语写作评价以教师书面反馈语法错误为主，学生被动学习，成效甚少，一线教师如何有效开展写作教学与评价的问题亟需解决。师生合作评价融合多种评价方式，自提出以来已被初步验证能够提高中学外语学习者的英语写作能力，但相关研究仍处于早期发展阶段，需要进一步验证其成效并探索相关实践问题，即如何满足不同层次学生学习需求与提高学生参与度。在此背景下，本研究拟解决以下三个问题（1）如何优化师生合作评价，形成基于差异化教学理论的师生合作评价教学模式，以满足不同学生的学习需求与提高学生参与度；（2）基于差异化教学理论的师生合作评价教学模式对初中生英语写作表现有何影响（包括内容、语言使用、篇章结构与交际有效性四大方面）；（3）基于差异化教学理论的师生合作教学模式对初中生英语写作能力有何影响（包括内容、语言使用、篇章结构与交际有效性四大方面）。本研究还旨在探讨学生对新教学模式的看法与该模式对学生英语写作自我效能感的影响。研究者通过三节课的课例研究将构建的教学模式付诸实践，以评促学，27名初中生参与了本次课例研究。
通过收集与分析课堂观察表、两次写作能力水平测试数据、学生在三次写作任务中的初稿与终稿、焦点小组访谈数据、问卷调查数据与其他实物数据，研究发现：（1）基于差异化教学理论的教学原则、合作学习的基本要素与克拉申的二语习得假说，优化师生合作评价教学模式是可行的；（2）基于差异化教学理论的师生合作评价教学模式对初中生英语写作表现有显著正向影响，高阶学习者在语言使用、内容、篇章结构与交际得体四个方面都得到了提升，中阶学习者提升了写作的语言与交际得体性，初阶学习者则在语言使用上取得了进步；（3）基于差异化教学理论的师生合作评价教学模式可能对初阶中学英语学习者的写作能力有显著正向影响，这一影响主要体现在语言使用和篇章结构上的改进。尽管该模式提升了中高阶学习者的平均分，但并未对其写作能力产生显著正向影响。研究还发现大多数学生认可这一学习模式并希望今后能够继续使用，该模式能够提高学生对英语写作表现的自我效能感。研究者结合相关文献对研究结果进一步分析，并提出三点实践建议（1）尽管将教育理论与实证证据融入日常教学充满挑战，其对促学具有极大意义，值得一试；（2）为了提高学生英语写作表现与能力，在开展写作教学与评价时需注意增进学生互动交流，引导学生建立积极的心理状态；（3）不仅需要关注初阶学习者的学习需求，还需要关注中阶与高阶学习者认知与情感双方面的学习需求。

Although Teacher-Student Collaborative Assessment (TSCA), a multiple writing assessment method, has been preliminarily validated to be effective in enhancing EFL (English as a foreign language) learners’ writing competence, research on it is still in its infancy. More research is warranted concerning further validation of its effectiveness and some unsolved issues regarding failures to attend to different learners’ needs and improve learner involvement. Practically speaking, brief teacher-written feedback on grammatical mistakes having dominated the Chinese EFL classroom, students find it difficult to learn from assessment. To address the research gap and improve writing instruction and assessment in practice, the present study aims to address the following three research questions (1) how to optimize TSCA and develop Differentiated-Instruction-Based TSCA (DI-Based TSCA) for the purpose of catering to students’ different needs and in-class involvement; (2) what are the impacts of DI-Based TSCA on junior high school students’ EFL writing performance, including aspects of content, language use, organization, and communicative effectiveness; (3) what are the impacts of DI-Based TSCA on junior high school students’ EFL writing competence, including aspects of content, language use, organization, and communicative effectiveness. Students’ perceptions of the constructed teaching model and its impact on students’ EFL writing self-efficacy were also investigated. The teaching model was carried out in a lesson study lasting two months. 27 Chinese EFL junior high school students participated in the three lessons.
Drawing on five sources of data consisting of classroom observation, EFL writing tests, focus-group interviews, questionnaire, and other physical materials, the major findings are that (1) TSCA can be optimized by incorporating principles of Differentiated Instruction, essential  elements of an effective cooperative learning activity, and Krashen’s hypotheses of Second Language Acquisition; (2) DI-Based TSCA was effective in improving EFL writing performance of students regardless of proficiency levels, with advanced students improving in all aspects (i.e., language, content, organization and communicative achievement), intermediate students making progress in the aspects of language and communicative achievement, and novice students achieving improvements in the aspect of language; (3) DI-Based TSCA can merely positively influence the writing competence of novice students in the aspects of language and organization, whereas it did not bring about a statistically increase in EFL competence of intermediate and advanced learners in spite of the increased mean scores. It was also found that most students were in favor of DI-Based TSCA and hoped to learn in the same way in their future study. DI-Based TSCA could positively influence EFL learners’ performance self-efficacy in writing. These findings are discussed based on relevant literature. Implications for EFL writing instructors and researchers are suggested as (1) it would be worthwhile to incorporate theory and research evidence into everyday teaching practices in a learning community despite the challenges that teachers might encounter; (2) more social interaction and students’ positive psychological state should be promoted in order to improve students’ writing performance and competence when implementing DI-Based TSCA and other types of writing instruction or assessment; (3) instructors should cater to not only novice students’ learning needs but also intermediate and advanced learners’ needs both in cognitive aspect and affective aspect.