The information on academic performance rates--what percentage of the enrolled credits a student can pass in one academic year--showed traditionally a relatively low students' academic performance at Spanish public universities. However, over the period 2008-2014, the academic productivity of undergraduate students at public higher education institutions improved considerably. In this period, Spanish universities experienced changes related to the structuring of the educational curriculum--the homogenization of undergraduate university degrees--and the policy of tuition fees. In relation to the latter, the entry into force of the Royal Decree-Law 14/2012 (the so-called "Decreto Wert") allowed universities a considerable increase in tuition fees. Using data for Spanish public universities for the academic years 2008/2009 and 2013/2014, this paper studied to what extent this educational law contributed to the improvement of the academic performance of undergraduate students. Using a stochastic frontier analysis for panel data, this paper showed that the increase in undergraduate tuition fees (first enrolment) acted as a catalyst in reducing the inefficiencies of the Spanish public university system.