Okay so I discovered this completely by accident when I was broke AF (usual Tuesday situation) - Egyptian national holidays mean FREE MUSEUM ENTRY and the tourism ministry extends it to tourists too!! Revolution Day July 23rd is the big one but there's also Sinai Liberation Day April 25th and a few others

Egyptian Museum at Tahrir normally costs 200 EGP but goes completely free on these days. Same with Saladin Citadel (usually 180 EGP) and Islamic Art Museum (60 EGP). Even when it's not totally free the discounts are insane - like 75% off entrance fees.

The Ministry of Tourism website lists official dates but honestly just ask at your hostel in Tahrir or Downtown - reception staff always know about free museum days. Plus student IDs work year-round at most places for 50% discounts anyway.

Saved me like 400 EGP that day which meant I could actually afford dinner at Koshari Abu Tarek instead of surviving on street bread lol. Pro tip: these free days get crowded with local families so go early morning for the best experience.