Thinking Through Science Guide and Text
Thinking Through Science: A Comprehensive Prehuman History is secular and research-based. TTS begins when Earth began and ends right before humans. TTS uses the geological timescale to thematically teach the fundamentals of the major sciences of botany, biology, geology, and climatology. The TTS Student Log enables students to explore the readings and demonstrate their understanding.
The spines of the curriculum are two important reference sources (sold separately): Prehistoric Life and Natural History, both by DK.
The second edition of TTS adds six critical thinking lessons that will help students develop their researching and logic skills. Additionally, each assignment is leveled by grade and interest level. Lessons can be taught by a teacher or lessons can be assigned for independent study.