This study aimed to analyze the declarative tactical knowledge in football of students from Amazonas of different contexts of practice. Participated in the research 45 subjects (15.53 ± 1.1 years) from the U-17 category. The study subjects were divided into two groups: Group 1 (N=22), composed of players who participates in a systematic football training outside physical education classes; Group 2 (N=23), composed of individuals who experience football only at physical education classes. Declarative Tactical Knowledge Test were applied, through the exposition of eleven match scenes to the players using a data-show, where each scene was paralyzed at the exact moment when the carrier ball player should decide "what to do". We used the Mann-Whitney test to compare the scores of declarative tactical knowledge between the two groups. Thus, it was possible to verify that Group 1 has a higher volume of training (p = 0.00) when compared with Group 2. However, we did not observed statistical differences between groups for the variables "Correct answers" and "Score" (p = 0.66 and p = 0.31, respectively). Thus, it can be concluded that, perhaps more important that the spend time in practice, there is a need to improve the quality experienced practice.