Abstract
Constructing well-formed sentences is an important element of writing. However, many students struggled with this skill. The purpose of this study were to design and evaluation of computer assisted logical sentence composing learning on the students' performance and motivation. Hence, based on Variation Theory, the eight categories logical sentence composing instruction were designed. To understand the effective of this instruction, the study was conducted in an elementary and the participants were 94 4th grade students from 3 classes. The control group was conventional instruction and a delay posttest. The experiment group implemented the logical sentence composing instruction during three months and conducted the pre/post/delay-test of sentence, ARCS motivation questionnaires, and interviews. The findings show that the experiment students' logical sentence composing has significant improvement and the results of ARCS questionnaire showed students regard the instruction were position: Attention (62.19%), Relevance (60.39%), Confidence (61.83%) and Satisfaction (62.19%). Further, this study discussed how to designed the induction and adopt the feedback to help students improve the sentences proficiency and capability.