This research is conducted due to de fact that teachers mostly used uninteresting materials in the classroom. As a result, the students were not really interested in writing. In addition, the materials were not suitable to the three phases of writing: the pre-writing, whilst writing, and post-writing phases. The model included in the materials was also not suitable to the student's needs. This research aims at finding out the validity, practicality and effectiveness of narrative writing learning materials which are based on the Thinking Ability Improvement Learning Model. The research was done at SDN 07 Padang Sago. The subjects were 18 third-grade students of the school. This development research applied the 4D model: define, design, develop, and disseminate. The materials' validity was analyzed from the lesson plan implementation sheets as well as the teacher's and students' responses sheets. Meanwhile, the effectiveness of the materials were analyzed from the activities, process, and the students' learning outcomes. Based on the validity test, it is found that the materials are very valid. This means they include all three writing phases, the language used is suitable to the Indonesian Standardized Spelling Rules and the graphics used the materials' match the students' age level. Meanwhile, based on the practicality test, it is easy for the materials are very practical since the lesson is chronologically ordered. Thus, it is easy for the teacher and students to comprehend them. Finally, the effectiveness test shows that the materials are very effective to improve the students' abilities in narrative writing. Overall, it is concluded that the materials are valid, practical, and effective. It is hoped that the materials can be used in the learning process at the school.