Video discussed seasons and where are there changes in seasons. The four seasons are; summer, fall/autumn, winter, spring. The northern and southern hemispheres experience opposite seasons. The seasons are caused by the tilt of the Earth at a 23 and a half degree angle and the orbit around the sun. Different parts of the Earth are closer to the sun at different times of the year. The seasons are measured in Equinoxes (March 21 and September 23) and Solstices (June 22 and December 22). Good video for any age student. (02:02)