Robots are a popular educational tool to introduce science, technology, and engineering to students. The field of educational robotics is growing and consequently a number of ducational robot kits have been developed within the last decade. Our laboratories have radition of teaching embodied artificial intelligence and biomechanics to students with different backgrounds. The robots we use both for research and education are usually built incorporating compliant materials as well as passive dynamics. These kind of properties are often not available in classical robot kits or mechanical construction kits. In this paper we describe some of the robots we use for education. So far we built the robots using 3D printing technology which is convenient but too expensive for class use. Our aim is to find cheaper, commercially available solutions. After a short review on educational robot kits and mechanical construction kits we describe interface solutions between several kits. Further we show some solutions to incorporate compliant materials and passive dynamics to traditional mechanical construction kits by using cheap and widely available materials.