This is the 309th most frequent German word.
jeder
"Jeder" means "each" or "everyone" in English.
In this sentence, 'jeder' is used to indicate every single day, signifying universality or regularity.
Jeder Tag bringt neue Möglichkeiten.
Every day brings new opportunities.
Here, 'jedem' is the dative case form of 'jeder', used in the context of giving something to every single student.
Ich habe jedem Schüler das Buch gegeben.
I gave the book to every student.
In this case, 'jede' is the feminine singular nominative form of 'jeder', referring to each individual person.