Background: Accurate calculation of dosages and safe administration of medications in clinical practice is an essential skill for the registered nurse. Appropriate educational preparation of student nurses is the key to ensuring they become safe practitioners in the workforce. A review of the literature on different approaches for teaching and assessing medication calculation with student nurses revealed three main factors that influenced student nurses' ability to calculate medications accurately and identify mistakes. These factors include mathematical ability, particularly around multiplying with decimals, understanding medication formulas, and conceptualising medication dose. Objectives: This study evaluated teaching interventions that focused on improving the students' understanding of mathematical calculations, medication formulas and conceptualising medication doses. Design: Evaluation study with teaching interventions and Time 1 and Time 2 medication tests. Participants: 156, 2nd year Bachelor of Nursing students from an Australian University Method: The teaching interventions over 8 weeks included teaching decimals and basic mathematical skills, using the correct mathematical formula for the medication and linking the medication to the patient case study. Time 1 and Time 2 medication tests out of ten, student demographics and reasons for attending tutorials were collected to evaluate the effectiveness of the teaching interventions. Results: For Time 1 medication test pre interventions, the mean was 7.3 with a mode of 8 out of ten. Maths and incorrect medication formula were the most common mistake. For Time 2 medication test post interventions, the mean was 9.3 with a mode of 10. The most common reason for incorrect answer Time 2 was incorrect medication formula. The students identified that the smaller tutorial sizes and remediation of errors was the main reason for continued attendance. Conclusions: The teaching intervention improved the accuracy of students' medication calculation, specifically, understanding the correct formula to use and identifying errors of calculation.