The old Second Primary School Celje was built in 1912 and it was situated in the town centre. During the war the building served as a kind of military hospital. Immediately after the war, however, the primary school under difficult circumstances started to work again. First, at the schoolyard, then the students and teachers moved into the school premises. In the early post-war years there were only two schools in Celje. With the upgrading of schools and school reform (in 1958) work started on the school surroundings. The number of pupils at the school declined from year to year.
Many schools used the school building; before the war it was a Commercial school; after the war it was an evening Polytechnic school, a Craft school, a School for teachers, and after The Pedagogical school centre it became the Department of Pedagogy of the Academy of Maribor. The crowding was great and there was a shortage of useful premises from year to year, and so it became necessary for new premises to be constructed.
In the year 1972 the cornerstone was laid in the media field where the school stands today. The Second Primary School was renamed Primary School Slavko Šlander, which was upgraded in 1974. The old building was left entirely for the needs of the middle school Celje.
In the educational field, everything has been done to facilitate the learners and give them an opportunity to acquire as many new skills as possible. Therefore, teachers continuously participated in upgrading their education, particularly in the context of professional school teams.Then our students started to prepare their research tasks at the municipal meetings of the Youth for Progress of Celje.
They were closely involved with the Pedagogical school centre in Celje and the Pedagogical Academy in Maribor. Students at the Pedagogical Academy had the opportunity to have excellent presentations at our school and they also had diploma exams for students of the fourth year.