This was a surprisingly challenging question. Philosophy is not often
taught in North American high schools, and there are many fewer
textbooks for this educational level than for college-level courses. I
have identified eight high school philosophy textbooks:
"Philosophy Made Simple"
Richard H. Popkin and Avrum Stroll
Doubleday, New York, 1993
"Does the Center Hold?"
Mayfield Publishing Co., CA, 1996/2002
"The Right Thing To Do"
"Philosophy: The Big Questions"
Frank Cunningham, Daniel Lalonde, David Neelin and Kenneth Peglar
Canadian Scholars' Press
"Philosophy 12: Questions and Theories"
Laura Gini-Newman and Paul Paquette
"Philosophy in Action"
Fitzhenry & Whiteside
"Fundamentals of Philosophy"
David Stewart, H. Gene Blocker
"The Philosopher's Way: Thinking Critically About Profound Ideas"
My list was compiled from these sources:
"Philosophy at the High School Level
In 1994 the OAC (Grade 13) Philosophy course was introduced to Ontario
high schools, making Ontario the first and only (English-speaking)
educational jurisdiction in North America to have philosophy as part
of its official secondary school curriculum. Since then, interest
in the course has grown rapidly. In 1998-99, for example, over 6000
secondary school students were enrolled in the course, in over 150
high schools across the province. In 1999, the Ontario Philosophy
Teachers' Association was founded, an association that hosts annual
conferences for high school philosophy teachers, and represents the
interests of high school philosophy teachers at the local, provincial
and national levels. In 2001-2002, with the introduction of the new
secondary school curriculum in Ontario, two new philosophy courses
were introduced to replace the OAC, one at the grade 12 level and one
at the grade 11 level.
Two new philosophy textbooks have accompanied the launch of the new
courses: Philosophy: Questions and Theories (McGraw Hill Ryerson,
2002), for the grade 12 course, and Philosophy: The Big Questions
(Canadian Scholars Press, 2003), for the grade 11 course."
York University: Philosophy at the High School Level
"Three key texts, authored by high school teachers and university
professors, are used in Ontario classrooms.
Frank Cunningham, Daniel Lalonde, David Neelin and Kenneth Peglar,
Philosophy: The Big Questions, ISBN 1-55130-230-6, Canadian Scholars?
Laura Gini-Newman and Paul Paquette, Philosophy 12: Questions and
Theories, ISBN 007-091386-2, McGraw-Hill Ryerson
Wayne Sproule, Philosophy in Action, ISBN 1-55041-109-8, Fitzhenry & Whiteside"
Ontario College of Teachers: Is philosophical inquiry really important?
Philosophy Made Simple, R. Popkin and A. Stroll, Doubleday, New York, 1993.
Does the Center Hold?, 2nd Ed./3rd Ed., D. Palmer, Mayfield
Publishing Co., CA, 1996/2002.
The Right Thing To Do, 2nd Ed./3rd Ed., J. Rachels, McGraw-Hill, 1999/2003.
Prerequisites: None. Grades 11-12."
Seoul Foreign School: Philosophy of Religion
Prentice Hall Online Catalog: Middle & High School Textbooks
My Google search strategy:
Google Web Search: textbook philosophy "high school"
I hope this is helpful. If anything is unclear or incomplete, or if a
link doesn't work for you, please request clarification; I'll be glad
to offer further assistance before you rate my answer.