The open hardware mobile manipulator (OHMM) is a new open platform with a unique combination of features for teaching robotics software and algorithms. On-board low- and high-level processors support real-time embedded programming and motor control, as well as higher-level coding with contemporary libraries. Full hardware designs and software source codes are available under free licenses enabling the community to adapt and update the design as the field (and available hardware) evolves. Digital manufacturing (3-D printing and laser cutting) methods, now available as low-cost Internet services, enable OHMM to be easily modified and to be built from scratch for a competitive price. Five hands-on curriculum modules are presented that use OHMM to teach robotics software and algorithms at the undergraduate and graduate levels, and results are presented based on student performance and feedback.