A Strange Instrument: The Steelpan / Mr. Denjiro’s Happy Energy! #504
3:01
A Mysterious Instrument: The Musical Saw / Mr. Denjiro’s Happy Energy! #499
8:20
遊びの科学/science of play
3:01
Chocolate that Makes Noise / Mr. Denjiro's Happy Energy! #671
3:06
Synchronization in Our Daily Lives / Mr. Denjiro’s Happy Energy! #825
3:06
Jumping from Up High with Just a Stick?! / Mr. Denjiro's Happy Energy! #823
14:01
THE MAKING（３１４）鋼球ができるまで
3:01
The Mechanism of Audio Feedback / Mr. Denjiro's Happy Energy! #476
28:21