
Japan has two official religions: Buddhism and Shinto. This is a Shinto Shrine. Shrines can range from massively big to cupboard-sized, like this one. They are all devoted to a different aspect of life. For example, this one is for good fortune. But they can be for anything from business, to love, to a famous person, to studying. And yes at university entrance exam time, the ones reigning over study are filled with high school students, praying to pass their exams.
Another major difference between the Buddhist temples and the Shinto Shrines is that you clap your hands when you pray at a shrine, but not at a temple.

These are Jizo statues. Jizo is a kind of healing stone. They are carved into the shape of a man and dressed with a red bib and hat. Sometimes these shrines pop up when accidents happened in order to heal the spirits around the spot.
Hanging on the sides of the shrine are
tsuru, origami cranes. They are associated with health. After the atom bomb was dropped on Hiroshima, Sadoko, a young girl who was afflicted by radiation and developed leukemia, tried to fold 1,000 cranes in an attempt to get well. Tragically she failed, but now school children all across Japan learn how to fold them and often send them to Sadoko's monument in Hiroshima's peace park.