Scholars have expressed widespread concern about voters’ ability to critically evaluate political messages, particularly in light of recent democratic outcomes such as the election of Donald Trump and the Brexit referendum. This study investigates whether written instructions alone—without interpersonal interaction—can enhance individuals’ ability to assess the strength of arguments. Drawing on the argument scheme approach and its associated critical questions, we establish a standard of argument quality and a method for evaluating arguments. In an experimental study, we test whether instructions on using critical questions improve participants’ evaluations of political arguments, and whether repeated exposure strengthens this effect. The results show that participants who received repeated instructions distinguished more clearly between low- and high-quality arguments than those who received instructions only once or not at all, suggesting an improved ability to evaluate political arguments.