新时代背景下的教育需要教学评价的改革，为契合核心素养导向下的人才培养目标，多元化的评价方式正受到越来越多的关注。同伴互评是早期写作课堂中常用的评价方式，随着时间的推移，逐渐被应用在其他领域中。这种评价方式能够解决教师主宰、评价流于形式等问题，能够提高学生的学习主动性、激发学生对自我的反思。然而在应用同伴互评策略时，其效果会受到众多因素的影响，分组机制就是其中一个主要因素。本研究以建构主义学习理论、支架式教学理论、反馈干预理论为指导，从初中信息技术课着手，探究不同分组机制（同质分组、异质分组、自由组合）下的同伴互评策略对学生的信息技术学习自我效能感、课程成绩和对同伴互评态度的影响是否存在差异。
       本研究选取宁夏某中学八年级平行班中三个班级的学生作为研究对象，开展了为期四个月的《图像的加工与处理》课程教学，并在课堂上实施同伴互评策略。研究过程中采用准实验研究法、问卷调查法和访谈法。三个班级分为三组，其中实验组A 45人，实验组B 45人，控制组45人。三个班级在采用同伴互评策略时依据学生上一学年综合成绩进行分组，实验组A进行同质分组，实验组B进行异质分组，控制组通过自由组合分组。三个班级在四个月各开展13次课程活动，实验中由同一位教师进行授课，采用同样的授课方式，在每节课的作品评价环节采用同伴互评策略进行。实验前后通过量表和问卷的形式得到与学生信息技术学习自我效能感、课程成绩以及对同伴互评态度的相关数据，最后进行分析。
      研究结果表明：（1）异质分组中学生自我效能感及成绩的提升高于其余两组。（2）异质分组对学优生与学困生的自我效能感影响作用最优，同质分组对学优生成绩的影响作用最优，中等生在三种分组中均不受影响。（3）不同分组机制下的学生对于同伴互评策略的态度不同，同质分组中大部分学生持否定态度。因此，教师在实施同伴互评策略时应注意综合考虑学生水平差异，注意确保组内人员异质，避免大范围的同质及自由组合分组，从而有效保证同伴互评的评价效果。

  It's necessary to reform the teaching evaluation under the background of the new era. In order to meet the talent training goals under the guidance of core literacy, diversified evaluation methods are receiving more and more attention. Peer assessment is a common assessment method in early writing classes which has been gradually applied in other fields as time goes by. This kind of assessment can solve the problems of teacher dominance and avoid assessment becoming a mere formality. Itcan improve students' learning initiative and stimulate students' self-reflection. However, the effectiveness of peer assessment is influenced by a number of factors, one of which is the grouping mechanism. This study is guided by constructivist learning theory, scaffolding theory, and feedback intervention theory. And this study explores whether there are differences in the impact of peer assessment under different grouping mechanisms (homogeneous grouping, heterogeneous grouping, and free combination) on students' self-efficacy in information technology learning, course performance, and peer assessment attitudes.
  This study selected three classes in the eighth grade of a middle school in Ningxia as theresearch objects. The course of Image Processing were carried out for one semester with the peer assessment strategy. The study adopts quasi-experimental research method, questionnaire survey method and interview. The three classes were divided into three groups, including 45 students in experimental group A, 45 students in experimental group B and 45 students in control group. During the peer assessment process, the three classes were divided into groups according to the students' comprehensive scores in the last year. The experimental group A was divided into homogenous groups, the experimental group B was divided into heterogenous groups, and the control group was divided into free groups. The three classes carried out a total of 13 curriculum activities
in four months. In the experiment, the same teacher gave lectures and adopted the same teaching method. Peer assessment was adopted in the evaluation of works in each class. Before and after the experiment, the data related to students' self-efficacy in information technology learning, course performance and attitude towards peer assessment were obtained by scales and questionnaires, and finally analyzed.
  The results show that: (1) Students in the heterogeneous group get higher self-efficacy and achievement than the other two groups. (2）Heterogeneous grouping has the optimal effect on the self-efficacy of excellent students and students with low score, and homogeneous grouping has the optimal effect on the performance of excellent students. Intermediate students are not affected in any of the three groups. (3) Students under different grouping mechanisms have different attitudes towards peer assessment, and most students in homogeneous groups hold a negative attitude. Therefore, teachers should pay attention to the difference of students' levels when implementing peer assessment and ensure the heterogeneity of the members in the group. In the meantime, they should avoid large-scale homogeneity and free combination grouping, so as to effectively ensure the evaluation effect of peer assessment.