Final answer:
The tip of a straight laryngoscope blade should be placed in the vallecula when intubating a pediatric patient to properly expose the glottic opening.
Step-by-step explanation:
When correctly placed for a pediatric patient, the tip of a straight laryngoscope blade should be in the vallecula, which is the space at the base of the tongue between the epiglottis and the posterior pharyngeal wall. This placement allows for indirect elevation of the epiglottis by lifting it anteriorly, which reveals the glottic opening for endotracheal tube placement. Placing the blade beyond the vocal cords or touching the uvula is incorrect and can cause harm, while aligning it with the epiglottis does not offer the same control or visualization of the glottis.