Quality education is one of UNESCO's goals for sustainable development, including in the science area. In order to achieve this goal, experimental activities are needed to produce dynamic, interactive, and more effective teaching. Brazil is a continental country with problems in assures education for all. In this work, with the aim of identifying student conceptions about the importance of practical classes, we performed a literature review and developed a research questionnaire for using with elementary school students from the municipal and state public schools in a Brazilian small town in the mountain region, located in the north-central region of the state of Bahia. The questionnaire contains subjective, semi-subjective and objective questions divided into categories: Profile (gender, age, grade) and Practical Classes (concept, importance, achievement). The questionnaire was applied to all elementary and high schools of the municipal and state public network located in this small town, together with the Free and Informed Consent Term (FICT), for the personal consent of students over 18 years of age, and in the case of underage students, the consent of parents and/or guardians. The results with the students from the final grades, respectively 9th year of 2 elementary schools in the urban area and 5 in the rural area, which made up all the elementary schools of this city at the time of the research, and students of the 3rd year of a high school revealed that they do miss practical class and know what is necessary to have those, despite their knowledge about of "what is a practical class" is not linked directly to disciplines such as biology. This work may contribute to stimulate the investment in laboratories at elementary schools not only in this small city, from a Northwestern state, one of the poorest countryside areas of Brazil, but also in other cities in developing countries.