Although zoos have an increasingly important role to play in educating the public about conservation and inspiring pro-conservation behaviour, they are not firmly established as leaders of conservation education. A multitude of logistical challenges and methodological limitations in zoological education research are contributory factors to this. However, certain research weaknesses can be minimized by collecting data from more than one source. The current research evaluated children's learning in a zoo and an aquarium using three different methodologies in one study: match pairs surveys, behavioural observation and conversational content analysis. The findings indicate that learning occurred in both the zoo and aquarium for most participants but was more profound for children who participated in an educational intervention. Importantly, the results of each methodology substantiate each other to definitively validate results and demonstrate the positive impact of a zoo or aquarium visit on children's learning. To produce more meaningful, reliable and valid research, zoological education studies should integrate mixed-methods and data triangulation into future research.