OK, besides the
trivia listed on ANN:
Episode 1: The most obvious thing, a PSP parody called PFP here.
Episode 2: Charles Schultz' Peanuts laugh:
Nice car.
Also, the school's called Maijima High. It probably doesn't indicate anything but Pinus Thunbergii Maijima itself is a Japanese plant. I'm probably misinterpreting / interpreting too much though.
Iron Maiden
À la Georges Seurat (Pointillism)
[I'm not an ace in Art so feel free to correct me if I'm wrong]:
Could this illustration of Mio be by Carnelian?
Episode 3: Heidi reference is just too good not to mention
Cinderella's pumpkin carriage:
This artist is familiar but I can't think of a name.
Episode 4: Indiana Jones
I don't know if it is but this pose somehow reminds me of Lelouch from Code Geass
Windows 7 Ultimate parody Widoes 7 Ultimate
Oppai Mouse Pad
To Heart 2 style by Mitsumi Misato. You see Konomi Yuzuhara on the PFP screen.