Supplementary Data for Instruction and Assessment without Calculators in an introductory microbiology course reveal student weaknesses in foundational quantitative literacy.

To preserve the integrity of exams after programmable calculators became ubiquitous, math-related microbiology exam questions were re-designed to allow for completion using only brief hand-written calculations and mental math. Students were advised at the beginning of the semester that lecture exams would be calculator-free, and were given questions for practice during and outside of class time. Although course prerequisites included high school math and chemistry, university-level chemistry and introductory genetics, students’ exam answers suggested unexpected weaknesses in quantitative literacy. Students were asked for permission to use their work in a six-semester study. Error analysis conducted on relevant assessment questions revealed difficulties with simple division, ratio set-up, dilution factors, unit conversions, concentration, and simple log and exponent calculations. During the final three semesters of the study, a simple preliminary math assessment was administered at the beginning of the course, to provide feedback to students and to determine whether their quantitative skills could be improved. A comparison of performance on the preliminary assessment questions versus relevant exam questions revealed that students could significantly improve their quantitative skills by the end of the course. This study is unique in its focus on calculator-free instruction, and assessment of fundamental quantitative literacy in post-secondary students.