The aim is to design, validate, and demonstrate both the feasibility and efficacy of an observational instrument in relation to the information provided by the teacher in the Physical Education classroom. The instrument "Hoja de observacion de video: intervencion didactica" was designed and five recorded Physical Education lessons oriented to health content were observed. The instrument showed validity and reliability concerning the information provided by the teacher who compiled content related to health and other content. A valid and reliable instrument for analyzing the information from the teacher related to health content is provided and moreover, the instrument's feasibility within the Physical Education classroom is confirmed for teacher evaluation.