One of the main concerns with youths is the nem-nems, which correspond to the group of youths that are not investing in their productive skills through the activities of either studying or working. This study analyzes data from National Household Sample Survey (Pesquisa Nacional por Amostra de Domicílios – PNAD), 1995-2015, to describe youth condition according to 4 categories: only study, only work, study and work, and nem-nem. An age-period-cohort model is considered to capture the influence of these factors on work/study decision trends. The year effects indicated that the decision to only work is pro-cyclical (i.e., tend to co-move with the economy), while that of being nem-nem or only studying are anti-cyclical. The results also showed that younger cohorts have higher proclivity to study and lower propensities to work and to be in the nem-nem condition.36 p. : il.