So i looked online and found some schedules of the classes, just to give everyone an idea of how it works i guess. Everyone in the same year goes to the same core classes, and then the electives are different!

[hider=Second Year Schedule]

NOTE: Second Years do not get to choose electives, but can join clubs/sports

Monday:
1-2 Charms
3 History of Magic
4 Astronomy

Tuesday:
1-2 Potions
3-4 Transfiguration

Wednesday:
1 Astronomy
2 Potions
3 Transfiguration
4 Flying*

Thursday:
1-2 Herbology

Friday:
1-2 Defense Against the Dark Arts 
3 History of Magic[/hider]

[hider=Fourth Year Schedule]

Fourth Years have more to do to prepare for O.W.L.S.

Monday:
1-2: Herbology
3 Care for Magical Creatures
4 Elective 1
5 Elective 2

Tuesday:
1-2: History of Magic
3: Potions
4/5: Elective1/Elective2

Wednesday:
1-2: Charms
3: Study Hall
4-5: Elective 1 - Elective 2

Thursday:
1-2: Transfiguration
3: Study Hall 
4-5: DATDA

Friday:
1-2: History of Magic
3: Charms
3-5: Double Potions
[/hider]

[Hider=Fifth Year Schedule]

Very important year, Take O.W.L.S. that will determine your career course

Monday:
1 History of Magic
2 Potions
3 Charms
4 Defense Against the Dark Arts 

Tuesday:
1 Charms
2 Transfiguration
3 Elective 1*
4 Herbology

Wednesday:
1 Free Period
2 Transfiguration
3 Herbology
4 Elective 1
5 Astronomy

Thursday:
1-2 Potions
3-4 Defense Against the Dark Arts 

Friday:
1-2 Elective 2
3-4 Elective 3
[/hider]

[hider=Sixth/Seventh Year Schedule]

Monday:
1 Defense Against the Dark Arts (E)
2 Elective 1* (P)
3-4 Potions (E)

Tuesday:
1 Transfiguration (E)
2 Defense Against the Dark Arts (E)
3 Free Period
4 Elective 1 (P)

Wednesday:
1 Charms (A)
2 Defense Against the Dark Arts (E)
3-4 Potions (E)

Thursday:
1-2 Elective 2 (P)
3-4 Elective 3 (P)
5 Astronomy (A)

Friday:
1 Transfiguration (E)
2 History of Magic (A)
3 Charms (A)
[/hider]

The Electives are:

Muggle Studies
-Divination
-Care of Magical Creatures
-Arithmacy
-Ancient runes

And you must select at least 2 if youre year 3 and up

EDIT: Years 1-5 are required to take Astronomy every Wednesday evening