Young children engage in incidental learning as they develop abilities to speak, play with toys and interact with their family and friends. Through unstructured play, they can learn problem solving, language use, social, physical and self-regulatory skills. Incidental learning is enjoyable and encourages curiosity. Game designers embed opportunities for incidental learning within computer games by setting challenges and offering rewards, as well as by providing landscapes to be navigated, rules to be inferred and the motives and actions of game characters to be interpreted. Incidental teaching is a form of behavioural therapy for children with autism. It involves creating an environment where children initiate ‘teachable moments’. Although incidental learning can enrich formal learning and occurs throughout a lifetime, it presents challenges for teachers and learners. Incidental learning takes place outside formal education, in the playground and at home.