The purpose of this research was to determine the effects of Cardio-Syntactic Analysis instruction on writing scores in an 11th grade English class. The sample consisted of 35 students enrolled in an Honor's English 11 class at Volunteer high School, in Church Hill, TN. The class was randomly assigned into an experimental group of 17 students and a control group of 18 students. The students in the experimental group participated in two days of intensive study of Cardio-Syntactic Analysis. Meanwhile, the control group worked on a game project that was due at a later date. The control group was not in the classroom during the instruction. After the instruction, both experimental and control groups were given a prompt, and 80 minutes to complete a well-formulated essay. Data were collected using a rubric to quantitatively score the essay. The rubric consisted of several categories. Data were then analyzed using t-test for independent means. The results indicated a significant difference between the experimental and control group for their performance. The experimental group outperformed the control group in the overall scores; similarly, they outperformed in the instructional categories taught within Cardio-Syntactic Analysis. The findings of the study suggest that secondary students could benefit from Cardio-Syntactic Analysis instruction in their English classes.