The questions was "what is global warming"? These websites over the course of a week helped me answer that question. There are strong opinions on both sides of this, so I wanted to give information, point out holes in the science, but ultimately leave Sam to form his own opinion.
What is climate? http://www.eo.ucar.edu/kids/green/what1.htm
Kid friendly climate and weather information http://www.weatherwizkids.com/weather-climate.htm
http://en.wikipedia.org/wiki/Climate_change To complex for us at this time - read the first paragraph or so.
Excellent experiment to determine what happens when polar ice melts. http://nicholasacademy.com/scienceexperiment215meltingicebergs.html
What David Suzuki says about climate change and climate change deniers. http://www.davidsuzuki.org/issues/climate-change/science/climate-change-basics/climate-change-101-1/
Basics Video - explaining science/modeling and what might happens http://www.sciencekids.co.nz/videos/earth/globalwarming.html This video says there is more to be learned about climate/global warming.
Use the pie chart to determine how most electicity is produced in North America. Are electric cars a good idea?: http://en.wikipedia.org/wiki/Electricity_generation
One Christian's idea about climate change. http://rebeccaluellamiller.wordpress.com/2010/05/10/embracing-climate-change/