The ability to follow instructions is essential for learning and classroom participation and, more broadly, for academic success. Yet, following instructions is challenging, especially for children, as it relies on working memory. In the present study, we used insights from working memory research to design and test ways to improve short-term maintenance of instructions in young adults (n = 40) and 9-year-old children (n = 40). Swiss-based participants memorized and executed sequences of spoken instructions under a baseline and three experimental conditions: additional free time, active verbal repetition, and passive repetition. In young adults, free time substantially improved performance. Passive repetition also improved performance, but not beyond the effect of free time. Active repetition, on the other hand, slightly impaired performance. In 9-year-olds in Switzerland, active repetition also impaired performance, but free time provided little benefit. These findings demonstrate that providing more free time during instruction delivery improves performance in young adults but is far less effective in children, suggesting important developmental differences in the short-term maintenance of instructions and the (strategic) use of free time.