You may say 'gakkou.'
学校 (gakkou) is the general name for school, however you will most likely hear people discussing different levels of school rather than saying just saying school.
小学 (shougaku, elementary school)
中学 (chuugaku, middle school)
高校 (koukou, high school)
大学 (daigaku, college)
大学院 (daigakuin, graduate school)
学校にいた is how you say I was at school in Japanese.
gakko no kamoku
Nyūsatsu no gakkō
Kurai kage gakkō
A school's "sports day" is called 運動会 (undoukai) in Japanese.
'Welcome to school' would be学校へようこそ (gakkou e youkoso) in Japanese.
Dojo, pronounced dough-joe.
Konesiwa da mean be sola
See the related link for Google's translation.
学校、素敵な学校 (gak'kō, suteki na gak'kō)
I am a Japanese high school student. High school in Japanese is Koukou. But it is pronounced Kohkoh, long vowels in Japanese are written with the first sound then a う (translates into a u sound) people writing it write the u and this gives the wrong idea, so once again it is said kohkoh like as in "oh, i didn't know that" that o sound
To say old Japanese illustrations in Japanese, you say "Mukashi no Nihon no irasuto".