Mahoraba 13
As the title implies, it's time for a treasure hunt! Kozue finds an old map of Narutakisou in her great-grandfather's diary and it seems to be a treasure map... though hard to read, and not really leading to any treasure at first... so everyone gives up for a bit, and Kozue, Shiratori, and Tamami go off to grab something at the shopping district nearby. While walking there Kozue tells them a bit about her great-grandfather. He was a very nice and caring guy, but he died when she was very young. Shiratori seems to remember something from that time... At the shopping district, Shiratori goes to buy some stuff to fix the door Momono broke, Kozue, a nice big watermelon for everyone, and Tamami, something from an electronics store. The watermelon guy tells the group a bit about the history Narutaki-sou. It was standing even after the war, and when developers tried to buy it to build big buildings, Kozue's great-grandfather stood up to them and that's why Narutakisou is still around even today.
After returning, Tamami takes out the extra-big zoom lens she bought for her camera to enhance the text on the map. Seems like only people like Kozue and Shiratori can find the treasure... no.. they just had to fold it the right way to find the location of the treasure ;) So the treasure is.... photos of the people who lived in Narutakisou before. So they were sent on a wild goose chase, and Kozue's grandfather and the residents then did the same thing, and left a photo of themselves there.
The previous residents of Narutakisou have an uncanny resemblence to the current residents. Though with Sayoko and Asami switched ;) Kozue and everyone else decide to put a picture of themselves in there for the next group of people to find...
This time was an anime original story, and didn't seem out of place at all. I wonder if there's something to the fact that Shiratori looks exactly like Kozue's great-grandfather or not, as well as the the other Narutakisou residents looking like the previous... We'll see :) And next time, "At Summer's End".
I find it interesting they switched around Asami and Sayoko's ages in the old photo of lookalikes. Essentially they're the same in the current generation since Sayoko's pretty helpless on her own and Asami takes care of both of them, poor Asami. :)