Most studies investigating the effects of environmental noise on children’s cognitive performance examine the impact of monaural noise (i.e., same signal to both ears), oversimplifying multiple aspects of binaural hearing (i.e., adequately reproducing interaural differences and spatial information). In the current study, the effects of a realistic classroom-noise scenario presented either monaurally or binaurally on tasks requiring processing of auditory and visually presented information were analyzed in children and adults. In Experiment 1, across age groups, word identification was more impaired by monaural than by binaural classroom noise, whereas listening comprehension (acting out oral instructions) was equally impaired in both noise conditions. In both tasks, children were more affected than adults. Disturbance ratings were unrelated to the actual performance decrements. Experiment 2 revealed detrimental effects of classroom noise on short-term memory (serial recall of words presented pictorially), which did not differ with age or presentation mode (monaural vs. binaural). The present results add to the evidence for detrimental effects of noise on speech perception and cognitive performance, and their interactions with age, using a realistic classroom-noise scenario. Binaural simulations of real-world auditory environments can improve the external validity of studies on the impact of noise on children’s and adults’ learning.