For adults wanting to understand what the greenhouse effect is all about, begin by watching the educational series of short video clips that begins with:
https://www.pbslearningmedia.org/resource/phy03.sci.phys.matter.greenhouse2/global-warming-the-physics-of-the-greenhouse-effect/#.XYQmICVOnDs
To summarize, short wave, radiant, visible light travels unimpeded thru the atmosphere striking and heating the Earth’s surface which then radiates heat back into the atmosphere as long waved infrared radiation where large atmospheric molecules like water vapor, carbon dioxide and methane slow down the escape of infrared radiation back into space. We had been living in the Goldilocks Zone of ‘not too much’ and ‘not too little’ of CO2. Not so, anymore.
Also, search:
samslair blogspot greenhouse effect