Timeline Issues
 

Usagi is 14 at the start of the series, but the show starts in Spring (Nar u mentions spring showers in like episode 6) so shouldn't Usagi be 13 when the series started?

Usagi and co spend their 8th grade year twice. Classic goes Spring (Jadeite episodes) Summer (Nephrite episodes) Fall (Rainbow Crystal episodes) Winter (Prince Endymion episodes) R goes Spring (Ail/En arc) Summer (early Chibi usa episode up till like episode 70/71) Fall (Episode 72- 77) Winter (episode 78-89). I've heard fanwanks that Silver Crystal actually rewound time back a year based on Usagi's wish but that doesn't really make sense because Makato is at Usagi's school, Minako is in Japan (and Sailor V still exists in video games and manga which shouldn't be possible) Naru and Umino are an item, Luna and Artemis are living with their respective owner. And the stage show in the penultimate episode of the Ail/En arc is based on Usagi's first adventure in episode 1.

They also don't enter high school until Sailor Moon Stars even though S took place in an entire calendar year.