This Motions of the Sun Lab is an interactive applet from the University of Nebraska-Lincoln Astronomy Applet project.

This NOAA visualization video on YouTube shows the seasonal variations in sea surface temperatures and ice cover for the 22 years prior to 2007 based on data collected by NOAA polar-orbiting satellites (POES). El NiÃo and La NiÃa are easily identified, as are the trends in decreasing polar sea ice.

An interactive simulation of Earth's seasonal dynamics that includes the axial tilt and other aspects of Earth's annual cycle.

This is part of a larger lab from the University of Nebraska at Lincoln: http://astro.unl.edu/naap/motion1/motion1.html

Hands-on laboratory activity that allows students to investigate the effects of distance and angle on the input of solar radiation at Earth's surface, the role played by albedo, the heat capacity of land and water, and how these cause the seasons. Students predict radiative heating based on simple geometry and experiment to test their hypotheses.