Peshat (פְּשָׁט) is the simple, surface meaning. These materials are straight-forward, explicitly articulating what they wish to teach you.
Peshat פְּשָׁט - when rabbis or educators try to directly apply a Kaplanian idea. For example, structuring a curriculum in a civilizational way, layering one civilization upon the other as they trace the evolution of key Jewish ideas and practices; Another example would be explicitly teaching a non-supernatural understanding of God.
Frequently Asked Questions of Reconstructionist Educators by Rabbi Moti Rieber, Rabbi Shai Gluskin and Dr. Jeffrey Schein
Biography of Mordecai Kaplan (5th - 9th grades) by Rabbi Lewis Eron