The manifestation Language Institute Days 2019, this year, as usually, officially begins on February 21, on the International Day of Mother tongue. This year, associates of the Institute held a series of lectures in primary and secondary schools in Sarajevo Canton. Ivana Tomić, MA, held a lecture on the topic “Beginnings of Slavic Literacy, the oldest written monuments of medieval literature” for the sixth grade of the Elementary School “Musa Ćazim Ćatić”. During the lecture she provided basic information about the work of the missionaries of Cyril and Methodius, letters – Glagolitic and Cyrillic, and spoke about the system of fonems in the Old Slavonic language. A special attention was given on the Humʼs plate and the Charter of Kulin ban. Children were assigned certain tasks, and they were dealing with the identification of word types in documents, and at the same time they also joined together to read, interpret and understand the literacy monuments. The pupils carefully followed the lectures and actively participated in the discussion. The teacher of the Bosnian / Croatian / Serbian language and literature, Malbina Sadiković, was also present at the time, and she prepared a very nice welcome.