We made a comparative study between two constructivists didactic design, for teaching the theme Heat in students of natural sciences careers. One with a integrated science focus and another with a non integrator focus. In the first design the student could build his own understanding, by solving problematical situations related to the biology and the natural environment, that allows him to analyze how are related the involucrated concepts, while in the second he build his understanding by solving physics but non biological problematic situations. We concluded that the first design allows to build in the students an cognitive structure of integrated type, wath makes it easier for them to internalize and transfer the physical concepts to problems of his specialty.
