Question

Why do the seasons change?

Answer 1

because earth tilts on the rotational axis which allows more sunlight on the northern side.

Answer 2

the way the earth is angled

Answer 3

the revolution of earth around the sun as well as the 23 degree tilt of earths axis (north to south pole). The suns rays hits the earth from different angles due to the tilt resulting in seasons. But the revolution around the sun is why it changes.