This is a pretty old wall I made several weeks ago. There's so few Bokura ga ita wallpaper out there I thought it would be nice to do one.

I drew the window, the chime and the little trees in Illustrator. Than in Photoshop, I textured the window by adding wood textures from photos I took. I tried to copy/paste as less as possible to make it more realistic. The birds pattern on the wall come from this site.
The birds in the sky are from a stock photo...
And finally I painted the scan to extended it and remove the grainess.

The window probably looks a little bit to sharp in comparision of the background, but since it's in front, let say the focus was made on it.

Scan : Cover of the first volume manga.