Neuroscience findings offer promising ways to enhance performance in educational settings. Adolescents often experience sleep deprivation, impacting memory processes crucial for learning. The synaptic homeostasis hypothesis (SHY) posits that non-rapid eye movement (NREM) sleep, particularly slow wave activity (0.5-4 Hz), downscales synapses potentiated during wakefulness, facilitating post-sleep encoding. Here, we evaluate the impact of a short nap on memory encoding of a biology lesson in a classroom setting. High school students were randomly assigned to a Nap group allowed to sleep (35-min sleep opportunity), or a Control group engaging in calm activities. Afterwards, they received the lesson, and were immediately tested. The Nap group showed better memory encoding, but this was not explained by NREM sleep. Instead, longer periods of NREM sleep showed a negative correlation with performance, possibly due to sleep inertia. Thus, while short naps can enhance academic performance, careful timing may help mitigate potential sleep inertia effects.