This study was motivated by the low accuracy of punctuation and capitalization usage in writing simple narrative texts among third-grade students at SDN Danau Ina. Most students still had difficulties placing periods at the end of sentences and using capital letters correctly at the beginning of sentences, names of people, and places. Some students also wrote capital letters in the middle of words incorrectly. In addition, students were not accustomed to rechecking their writing, resulting in many punctuation and capitalization errors. This study aimed to improve the accuracy of period and capitalization usage through the implementation of a checklist-based drill method. The research employed Classroom Action Research (CAR) using the Kemmis and McTaggart model conducted in two cycles consisting of planning, action, observation, and reflection. The subjects were 21 third-grade students of SDN Danau Ina. Data were collected through tests, observations, and documentation. The findings showed that the checklist-based drill method improved students’ ability in writing simple narrative texts. In the pre-test stage, the average score was 58.17 with a learning mastery percentage of 9.52%. In Cycle I, the average score increased to 71.19 with 52.38% mastery, while in Cycle II it increased to 90.1 with 95.24% mastery. Teacher activity also improved from 77.45% to 95.84%, while student activity increased from 72.34 to 89.93.