La incorporación del niño de preescolar al primer grado, ha sido durante muchos años un problema que ha despertado preocupación en el ámbito educativo, existe un cambio brusco de escenario y de estrategias de enseñanza. El objetivo fue crear un aula conjunta con niños y niñas de preescolar y de primer grado. El procedimiento consistió en aplicar estrategias de intervención pedagógica en el proceso de enseñanza de la lectura, escritura, operaciones lógico-matemáticas y ambiente de aprendizaje. Se desarrolló en tres momentos: a) Inicial b) Desarrollo y c) Final. Los resultados evidenciaron que los alumnos(as) de primer grado en ambientes y estrategias similares a las de preescolar, son determinantes para una adecuada articulación preescolar - primer grado; los niños de mayor competencia fueron mediadores efectivos para promover aprendizajes. Palabras clave Integración Aula conjunta ABSTRACT A PRESCHOOL - FIRST GRADE INTEGRATED CLASSROOM The incorporation of children coming from Preschool to the first grade of Elementary Education has been, during many years, a problem that has awaken the concern among parents, teachers and education managers, since there is a rough change of scenery in the educational environment and the teaching strategies. The project Integrated classroom preschool - first grade has as its main objective to create an integrated classroom attended by boys and girls from the kindergarten level and first grade. The research procedure consisted of applying strategies of pedagogical actions in the process of teaching reading, writing, logical-mathematical operations and the learning environment. It took place in three moments: a) initial b) developmental c) the final . The results showed evidence that boys and girls in first grade in environments similar to the ones in preschool, with teaching strategies that respect the growing and learning building processes, are crucial for an adequate preschool - first grade articulation; similarly, it is concluded that the children with a higher competence are effective mediators in the promotion of learning. Key words Integrated Classroom