Sample preparation is a key step in most biological experiments, including in the subject of lipidomics. Lipidomics focuses on the study of lipids produced in specific organisms, so samples required in lipidomics experiments are usually solutions of biological lipids. To make sure that the scientific experiments are reliable, lipid samples in a set of controlled experiments must be standardized, that is, have almost the same quality. Preparing standardized samples is therefore an important taught component in most undergraduate as well as postgraduate programs in lipidomics. Previously, the standardization of lipid samples has only been assessed qualitatively. How to evaluate the effectiveness of students' standard operation training is crucial. In this paper, we propose a quantitative assessment metric and process for preparing standardized lipid samples, which is further evaluated in our teaching practice. We find out that the proposed method is effective, with the help of which we can identify gaps in our teaching.