Ichiroh! is the story of two friends in Japan who both fail their college entrance exams. In Japan, entrance exams are a big part of the education process at every level. You need to pass the exam for a school to get into it. Due to this, there is a big industry for "cram schools" and "prep schools". The difference between the two being basically that the cram ones are attended in conjunction with regular schools while the prep schools are attended by those who are done with their schooling and wish to be taught well enough to pass the entrance exam mentioned already. A somewhat example of this in America is places like various "learning centers" where kids can be taken by parents after-school to be tutored.
Anyways, after our two characters, Nanako and Akane, fail to get into college, they decide to attend prep school together and share a dorm room. Nanako finds a great price for a female dorm, and is excited... until she and Akane get there. You see, what she didn't know was that to qualify for the lower room and board, she and Akane have to work as shrine maidens at the Shinto shrine attached to the dorm. If they don't want to work there, that is fine, but the prices go up.
So begins the efforts to prepare to get into school while working at the local shrine. This is an interesting premise, to be sure. But like with K-On, where the student band is merely a plot device for the interpersonal relationships of the characters (though it does have some impact on said plot), the situation here is just to put characters in a situation where we can watch them be funny and cute.
Like K-On, the same type of teasing of Yuri subtext and jokes about said stuff, relying almost on a mild form of "cringe comedy", is present. Also, there are other jokes that are sometimes funny to all, and at other times, particularly funny to Japanese audiences more so than American ones.
Above all, the just daily lives and friendships are important to the plot. Though, to be fair, not so much as in K-On. A good way I could describe it is that K-On focused more so on friendship over humor, while Ichiroh! focuses more on humor over friendship, but each manga is filled with both elements.
The only problem I had was not really a problem but one that may irk some in the non-Japanese West. The humor is funny, but some might interpret it to be homophobic. I don't, because I don't think that is intended that way, and Japan has different "buttons" than, say, America. Though they are more closeted (sadly) than America due to social pressure, I don't think that is at play here. I think it more likely that it is the Japanese penchant for mocking anything not in their own sacred cow listing (just like us and everyone else). My point is that I hope some don't interpret mild jokes (certain less than what some get from tv at their expense for other areas) don't ignore a cute, fun, and heartwarming story due to a few jokes. I can understand we all have our own berserk buttons though, so I am warning ahead of time.
I truly loved this series and I just can't recommend it enough.