Most out-of-hospital cardiac arrests are attended first by bystanders who are usually friends and/or relatives of the victim. Therefore, the objective of this research was to analyse the impact of a training process based on the flipped classroom on basic life support skills in primary education students. The sample consisted of 308 children (148 experimental group (EG) and 160 control group (CG)) between 10 and 13 years old (M = 10.68 ± 0.64) from 2 schools in Galicia, Spain. The data reveal that the quality parameters are obtained in the number of total compressions in 2 min (CG = 213 and EG = 217; p = 0.024) and in the percentage of correct compressions (CG = 87.23% and EG = 91.6%; p = 0.013) except for the mean depth and the percentage of correct compressions, which were not reached in any case. Regarding the application of an effective discharge with the Automated external defibrillator (AED), there were no significant differences in the time used by schoolchildren between both methods (p = 0.795), but 97.5% (n = 156) of the CG and 100% (n = 148) of the EG are able to do it in just over 1 min. Based on the results obtained, we can conclude that a training program based on the flipped classroom is as effective and viable as traditional training in psychomotricity on CPR techniques and the application of an effective discharge using an AED.