This article considers student analogical reasoning associated with learning practice in creating bio-inspired robots. The study was in the framework of an outreach course for middle school students. Fifty eighth and ninth graders performed inquiries into behavior and locomotion of snakes and designed robotic models using the BIOLOID robot construction kit. We analyzed the interdomain analogies between biological and robotic systems elaborated by the students and evaluated the contribution of the analogies to the integrated learning of biology and robotics. The analogies expressed by the students at different stages of the course were collected and categorized, and their use in knowledge construction was traced. The study indicated that students' reasoning evolved with learning, towards an increased share of deeper analogies at the end of the course. We found that analogical reasoning helped students to construct knowledge and guided their inquiry and design activities. In the proposed framework, the students learn to inquire into biological systems, generate analogies, and use them for developing and improving robotic systems.