Kimi ni Todoke - From Me To You

Both are about a girl who is an outcast in school though they have very opposite perceptions about friend making. They both also have a very popular male lead who is curious about the girl and wants to befriend her. 

I agree, Suki-tte Ii na yo totally reminds me of Kimi ni Todoke, outcast girl being chased after by the most popluar boy of school.

Similar basis for the stories. Both shows are pretty cute, although Kimi ni Todoke is more innocent. 

Both Sawako from Kimi ni Todoke and Sunako from Yamato Nadeshiko Shichi Henge are female protagonists who give off an extremely creepy vibe. While this is well-founded in the horror-loving Sunako and completely wrong for Sawako, this ongoing creepy theme is prevalent in both series. Also, while they are handled differently, both are ezzentially about male protagonists attempting to transform a socially awkward girl. If you enjoyed one, it's well worth watching the other.

Both of those shows focus on a gloomy, "sadako-like" girl without much self-confidence. Due to influence of a certain boy (or a group of boys in Yamanade) she gradually changes her ways, becomes more open and learns how to loose the "ghost" aura in order to show her beauty.The main difference is that Yamanade main focus is comedy, and Kimitode main focus is heartwarming. Still, both are entertaining shoujo stories with "if-you-make-effort-you-can-change-and-make-friends" theme.

Yamato Nadeshiko Shichi Henge and Kimi ni Todoke have very scary girls as the main heroines, or at least everyone believes them to be scary.  The male protagonists in the story are attempting to change the socially awkward girls into something'normal' for the society around them.  Neither one of the heroines have very much self-confidence in themselves which makes it hard for them to make friends.  The journey to change is what is exciting about each of the series.

These series both focus around a girl in a strange erm... school. Furthermore, each series contains a lot of extraordinary characters and great humor. If you enjoyed one series, you'll surely enjoy the other.

Kimi ni Todoke and Kaichou wa Maid-sama! Are similar to me because of the relationships between the characters.  The relationships that develop in the school settings and the support system that the main female protagonist is given from the ‘hero’ of the series.

While the art style is similar for both of these series I'd say the biggest thing that stands out for me is how the guys in these anime give the leading lady a softer edge. Truly showing the vibrant colors of the protagonists.