Since you are reading Table 1018.1 to require a 1-hour rating, I assume that the corridor serves an occupant load of more than 30 and that the building is not sprinklered. Does each classroom have an exit door directly to the exterior? If so, the building would meet Exception #1 and no rating would be required.
If it doesn't meet the exception, then the corridor walla are fire partitions (not fire barriers), and must comply with section 708. Section 708.6 sends us to section 716 for openings.
Section 716.5.3 tells us that the opening protectives in corridor walls are fire doors, and must have a fire protection rating of at least 20 minutes where located in corridors or smoke barrier walls in accordance with Table 716.5.
Looking at Table 716.5, I have to scroll down almost to the bottom to find Fire partitions: Corridor walls. For corridor walls rated 1 hour, the minimum fire door rating is 1/3 hour [20 minutes]. There's a footnote. but that just refers to section 716.6.3 for testing requirements.
Fire doors must be self-closing and self-latching. If you want them to remain open, they'll have to be on magnetic hold-opens that release upon activation of a fire alarm or smoke detector.