This article describes HOPSCOTCH, a design concept for an "exer-learning game" to engage elementary school children in learning. Exer-learning is a new genre of digital learning games that combines playing and learning with physical activity (exercise). HOPSCOTCH is a first design concept for exer-learning games that can be applied to support the acquisition of factual knowledge. HOPSCOTCH is based on the popular playground game in which a course is drawn on the pavement with numbers that indicate the course to be hopped. In two exploratory studies at a German elementary school, we investigated the potential of HOPSCOTCH to engage students, as well as to facilitate the acquisition of factual knowledge (English vocabulary) and to improve the attitudes of students towards learning English as a second language. The results of these studies indicated that the students remembered and correctly spelled about the same number of new vocabulary words after learning with HOPSCOTCH as they did after a teacher-centred lesson. Importantly however, the students enjoyed playing this exer-learning game very much and they reported better attitudes towards studying English after learning vocabulary with HOPSCOTCH compared to a teacher-centred lesson. These encouraging first results support the assumption that HOPSCOTCH as a design concept may have the potential to actively engage players in learning activities leading to a virtuous circle of reduced low level disruption and self-exclusion, increased assimilation of knowledge and greater engagement in lessons to the benefit of the whole class, not just the better-motivated individual. As such we suggest that exer-learning games could serve as additional classroom control and teaching aids in schools.