This article aims to show some activities based on non-routine problems with different levels of difficulty and from different classes that are integrated into the curriculum, additionally two spaces were opened for students to interact with recreational mathematics activities with the purpose of providing opportunities to all students access the robust construction of the concepts involved. These activities showed significant improvements in the learning of some mathematical concepts such as: operations with fractions, order in fractions, part of a number, ratios and proportions, percentages. In addition, there was evidence of an increase in the opportunities that students found to participate and favor the autonomy of mathematical thinking. This research was carried out in a public school in the city of Bogotá Colombia of low strata in the sixth grade of basic education, the activities designed in order to strengthen the robust concepts of fractions and decimals through different challenging problems will be shown, also called non-routine problems.