In health courses, the students must be familiar with the effects of intravenous solutions on cell volume and function, a topic where there can be learning difficulties and misunderstandings. Since educational games can assist in understanding complex concepts, we created a game relating solution osmolarity and tonicity to red blood cell volume that was used in undergraduate Dentistry and Medicine courses. The students, working in groups, completed the game board by indicating the effect of the solutions on the red blood cell volume and classifying the solutions in terms of tonicity and osmolarity. The student indicated that the use of the educational game contributed to their understanding of osmolarity and tonicity.