Kobudo means "way of weapons". In MojuKai we study and teach ancient Okinawan weapons as well as karate, which means "empty hand". Training with the traditional weapons offers additional skill sets to our students; it also assists with developing proficiency in empty hand techniques. By learning proper techniques with the various weapons (bo, tonfa, nunchaku, sai and kama) the gakusei (student) improves precision with their empty hand techniques.
MojuKai begins kobudo training with the bo, which is a wooden staff (it is incorrect to call this a "bo-staff" as both words have the same meaning). We begin with bo because it is the only weapon held by both hands simultaneously, which gives the practitioner better control while promoting use of the whole body to develop proper technique. This is the fundamental principle of Japanese / Okinawan systems. This is also the most practical weapon to learn because similarly shaped objects surround us and can be fashioned into a bo.
Tonfa translates into "handle". It should be easy to understand why.
Torque and power are easily developed with tonfa which is why police forces worldwide began using them. Tonfa are also easy to control, which is why they are taught after bo.
Nunchaku (NOT nunchucks and certainly not "numb-chucks") are the most well known of the martial arts weapons - thanks in large part to Bruce Lee who popularized them in his movies and famous movie posters. Nunchaku are flailing instruments and can be transitioned from hand-to-hand. Compared to bo and tonfa, the nunchaku can be used in a wide variety of ways and are therefore taught as intermediate weapons.
Sai are miniature pitchforks which are,like the tonfa, generally kept in one hand. However, the techniques are more diverse and complicated. These are intermediate to advanced level weapons due to the complexities of the techniques.
Kama are sickles (obviously). Kama techniques include slicing, stabbing, and twirling motions (for complex transitions). It requires advanced training to develop proficiency in kama making this an advanced level weapon.
In addition to kata training for learning the techniques of these weapons, once a student achieves black belt (Yudansha) level, they also learn drills pitting weapons against weapons. This is one of the favored practices for Yudansha.