In this paper we describe student use of a series of connected online problem-solving activities to remediate atmospheric carbon budget misconceptions held by undergraduate university students. In particular, activities were designed to address a common misconception about conservation of mass when students assume a simplistic, direct relationship between atmospheric CO₂ concentrations and carbon emissions. This particular misconception was challenged through an instructional intervention applying constructivist learning theory principles in an effort to prompt cognitive dissonance and induce conceptual change. This study is based on 1 y of data collected from a survey completed by introductory physical geology students (n = 176), divided into a control group (n = 127) and an experimental group (n = 49). The students in the experimental group worked on an instructional intervention targeting identified misconceptions during a laboratory session. Both the control group and the experimental group were presented information targeting the same misconception through a traditional lecture. Students completing the instructional intervention demonstrated significant increases in learning and reductions of misconceptions relative to students in the control group. However, some aspects of the misconceptions seemed to persist.