How did Menma die in Ano Hana? I do not remember any scene showing how Menma died. In the series, I could not figure it out. The scene described in Menma's death is showing a sandal beside river. If she drowned in the river, then when and how?
As Senshin already mentions. It is never explicitly stated how Menma died exactly.
However certain events, and symbolisms do hint towards how she most likely did die. The most common one being the slipper next to the river bank, implying that she fell/drowned in the river.
During the anime there were several events hinting to this happening as well.
- Poppo mentions that he saw Menma drifting away on the day she died
- Jintan almost fell into the river while running to find Menma
- Jintan catches Anaru as she almost slipped down this same hill
All these events together make it all the more likely that she tripped and fell down into the river. Whether she had been passed out due to the fall, just couldn't swim, or couldn't beat the river streams, is something we most likely will never know.