Wakuwaku-za

This family-friendly museum presents the history of Kumamoto and the castle from many angles, from the 10-minute video with English subtitles explaining the castle's construction and history, through the Satsuma Rebellion, to a 'projection map' showing the destruction wrought by the 2016 earthquakes. Elsewhere are dress-up opportunities for photo ops and close-up views of architectural features. A lot of it is targeted at Japanese kids, but there's plenty for other visitors, too.