I have a Master of Science (MS) in environmental policy from Florida International University and PhD in Religious Studies (with a focus on environmental ethics) from McGill University.  

I taught environmental history to undergraduate and graduate students at McGill for over a decade in courses such as ENVR 203 - Knowledge, Ethics, and the Environment, and ENVR 400 - Environmental Thought, and NRSC 512 - Water: Ethics, Law and Policy.   

These very texts (see sources) used for those university courses have been adapted for High School age learners.  

Ponting, Clive.  2007.  A New Green History of the World.  New York: Penguin Books.  

McNeill, J.R.  2001.  Something New Under the Sun: An Environmental History Of The Twentieth Century World.  WW Norton.

Diamond, Jared.  2011.  Collapse: How Societies Choose to Fail or Succeed: Revised Edition.  Penguin Books.  

Sen, Amartya.  1999.  Development as Freedom.   Anchor Books.

Nikiforuk, Andrew.  2012.  The Energy of Slaves: Oil and the New Servitude.  Greystone Books.  

Suzuki, David.  2022.  The Sacred Balance, 25th anniversary edition: Rediscovering Our Place in Nature.  Greystone Books.

Suzuki, David and Holly Dressel.  2010.  More Good News: Real Solutions to the Global Eco-Crisis.  Greystone Books.