Communication is a great value of the whole humankind. People who communicate well are able to convey their knowledge and ideas to other people. Good and quality communication is necessary for functioning in all spheres of the social life, and at the same time for the functioning of the pedagogical-educational process. The research has been conducted for determining which types, i.e. what sort of communication is dominant in the relation principal - students. The sample included 590 students of primary and secondary school and 14 principals from the region of Herzegovina (Bosnia and Herzegovina). Licker's scale was used for gathering data. Results of the research showed that communication between principal and students, there was democratic, direct and non-violent communication between principals and students. Communication between a principal and students is still the area, which is not given great significance. Most often, the accent is on communication between students and teachers, avoiding the analysis of communication between students and principals. Although in the pedagogical-educational work, communication between students and teachers is dominant; our opinion is that it is necessary to develop this communicational area as well. Quality communication at school should be a strategic point of principals, and it should be planned and applied consciously and continuously.

ABSTRACT The pulverized peel of unmodified and modified pumpkin (Cucurbita pepo L.) was used as sorbent for the determination of Cd, Co, Cr, Fe, Mn, Ni, and Pb by flame atomic absorption spectrometry. The parameters affecting the preconcentration efficiency were investigated. The optimal conditions for preconcentration on unmodified pumpkin peel were identical to those using modified peel: a pH of 8, a preconcentration factor of 10, a flow rate of 3 mL min−1, and an eluent concentration of 1 mol L−1 for all analytes. The detection limits of the method were 9.2, 8.8, 13.2, 28.7, 6.6, 7.6, and 16.5 µ g L−1, while the quantification limits were 30.6, 29.2, 43.9, 95.5, 22.1, 25.4, and 55.1 µ g L−1 for Cd, Co, Cr, Fe, Mn, Ni, and Pb, respectively. The accuracy of the method was verified with a certified reference material. The relative standard deviation was less than 4% based on 12 measurements. Under the optimum conditions of preconcentration, the recovery values exceeded 94%. The following capacity order was obtained for the analytes (µmol g−1): Ni2+ > Co2+ > Fe3+ > Mn2+ > Cr3+ > Cd2+ > Pb2+.