This paper presents results from two samples of adolescents aged 13–16 from Romania and Spain (N = 930 + 1,945 = 2,875). The original 7-item version of the Personal Well-Being Index (PWI) was used, together with an item on overall life satisfaction (OLS) and a set of six items related to satisfaction with school. A confirmatory factor analysis of the six school satisfaction items shows good fit statistics when relating them to a latent variable. However, said latent variable does not show a good fit when related to the OLS or the PWI. Tests have led to the conclusion that the item that best summarises satisfaction with school is “satisfaction with my life as a student”. Adding this item to the PWI-7 has shown a good fit with Structural Equation Modeling and higher standardised loading on the OLS. The analysis developed here, while confirming that the inclusion of a domain on satisfaction with school life contributes to the PWI with unique variance (2.5 % in this research), also offers an explanation for the surprising results obtained for adolescents in other countries (e.g. in Australia, Tomyn and Cummins in Soc Indicat Res 101(3):405–418 2010) by showing that satisfaction with friends at school and satisfaction with classmates did not significantly contribute to satisfaction with school. Our results suggest that school satisfaction is highly related to satisfaction with teachers, but weakly related to overall life satisfaction, while satisfaction with school friends and satisfaction with classmates are highly related to overall life satisfaction, but weakly related to satisfaction with school. Satisfaction with life as a student seems to be the item that best reconciles this “paradox” (in adults’ eyes), at least with our samples of Romanian and Spanish adolescents.