Objective: The aim of this study is to determine whether a one-hour image-rich didactic lecture given to sonographers can successfully teach them the TI-RADS (Thyroid Imaging, Reporting and Data System) lexicon, to improve their recognition of malignant thyroid nodules. Methods: A one-hour image-rich didactic lecture on TI-RADS was designed that encompassed the diagnostic criteria for thyroid malignancy and technical tips to better demonstrate thyroid nodules. A lecture was presented to 34 sonographers across multiple sites. The study examined the effects of the lecture by comparing the results of a pretest, an immediate posttest, and a two-week delayed posttest. Results: All 34 sonographers participated in the lecture intervention and each assessment. The prelecture assessment scores ranged from 13% to 73% with an average of 46%. Immediately after the lecture, the assessment scores ranged from 27% to 100%, with an average of 77%. Two weeks after the lectures, scores ranged from 27% to 93%, with an average of 70%. Compared to the pretest, there was a statistically significant increase in average scores immediately after and two weeks after the lecture. Conclusion: It is critically importance to have a reliable, noninvasive method to identify thyroid nodules that have a greater chance of malignancy. A didactic lecture could successfully teach, result in knowledge retention, and increase sonographers’ confidence in the TI-RADS lexicon.