The dynamics of task performance among boys during their second year of studying at educational establishment Journal title: Slobozans`kij Naukovo-Sportivnij Visnik [Slobozhanskyi Herald of Science and Sport] Authors: Elena Klyus| Тернопільський національний педагогічний університет імені Володимира Гнатюка Subject(s): Education, Sports and Recreation, Rehabilitation, Health and Wellness