The purpose of this dissertation is to study the following educational policies aimed at high school, focusing on the analysis of high school reform and its implementation in the state of Mato Grosso. The reform came about via Provisional Measure (MP) number 746 of 2016, and is part of the Federal Government s recent management strategies aimed at improving the quality of education, involving the restructuring of this teaching stage. In methodological terms, it is a qualitative research that accompanied the initial process of implementing the reform of high school, based on the analysis of national and state documents and interviews with high and middle level actors from the State Department of Education of the State of Mato Grosso (SEE-MT). The context of implementation of the reform involves rules, federative relations between the Federal Government and the State and between the State and the Municipalities, in addition to state bureaucratic and non-state actors, which are analyzed based on Political Science references, notably from the ambiguity-conflict binomial of Matland (1995), of the relations between federal layers and bureaucratic levels of Hupe and Hill (2003) and of the view of public policy as an incremental process by Lindblom (1979). It is concluded that the implementation of the reform of secondary education in the state of Mato Grosso has, at least, two remarkable characteristics, which can be interpreted in the light of the categories experimental context of implementation, incrementalism and the relationships that are established between the state and the Federal Government. High school reform takes place in Mato Grosso in a context of experimental implementation. In addition to the reform presenting a low degree of regulation and induction by the Federal Government, which makes its proposal more ambiguous, there is a low level of questioning in the state about the need for reform. It is a context in which the ways of implementing the reform do not yet have a precise definition by the Federal Government and seem to follow the same incremental logic that has been adopted by the state in the very change initiatives that have already been happening in high school. There are few previous state initiatives for change in the state high school of Mato Grosso and those that exist happen incrementally, little by little, following the capacity of induction and incentive of the Federal Government and experience accumulated by the state. This means that, at this stage of implementation, the state of Mato Grosso is giving priority to those dimensions of reform that are more in line with initiatives already underway and also more adherent to MEC s proposals, as is clearly the case with the expansion proposal of offering full-time schools.