The purpose of this action research project was to determine the impact of brief, targeted explicit grammar instruction on Spanish I students’ achievement in the acquisition of a foreign language. The research was conducted in the action researcher’s classroom, in a 3A school district in rural Iowa with 88 participants, aged 14-17. Students were split into two groups; one receiving implicit grammar instruction and the other receiving brief, targeted explicit grammar instruction in addition to the implicit grammar instruction. Quantitative data was collected throughout a unit from four main teacher-created summative assessments centered around the four domains of language; baseline data from a previous unit was also collected and analyzed. The findings indicated that a combined approach to grammar education can help learners more efficiently improve their Reading and Writing abilities when compared to a purely implicit approach. At the same time, learners’ Speaking abilities were negatively impacted, indicating that when using a combined approach to grammar instruction, it may be beneficial to incorporate more speaking activities.