The present research explores benefits of using young students' drawings in combination with written responses for gathering information about science concepts. Younger students are still very limited in their verbal expression and less biologically literate than older students. The aim was to determine primary school students' conceptions about owls, experiences with owls and their sources of information, and to then determine how beneficial it is to combine information gathered from drawings and written responses in comparison to previous research done with lower secondary school students. Altogether, 280 students attending fourth and fifth grades from schools in Slovenia participated in the research. Students knew well the specific features of owls. Drawings provided more clear information about body parts and proportions, while owls' specific habitats, behaviours and diet were more thoroughly described in their written responses. Students without experiences with living owls represented owls less thoroughly. Comparison of frequencies of responses in main categories of conceptions about owls showed that using drawings and written responses is equally beneficial for younger and older students. Gathering primary school students' conceptions about science concepts with both drawings and written responses enables better assessment of a student's knowledge than using just drawings or written responses.