Cycles in Science Books in Order
Cycles in Science is a 4-book series by Peter D. Riley for ages 9–12, at a grades 6–7 reading level, with gentle to intense content (HootRated intensity 1–4 out of 5).
- Books
- 4
- By publication date
- Content intensity
- Gentle to intense
- HootRated 1–4 out of 5 · avg 1.8
Cycles in Science Reading Order
Series numbers aren't available for most Cycles in Science books, so they're listed by publication date (oldest first).
Content Intensity Across the Series
VariesContent intensity ranges from Gentle to Intense across the series.
Series books grow with readers — but that's also the trap. Most series start at one reading level and one content intensity and drift upward over the course of the run. Cycles in Science (4 books by Peter D. Riley) lands at a grades 6–7 reading level, with average content intensity 1.8/5. Intensity varies from book to book, so check individual ratings in the list above.
The reading-order table above lists every book with per-volume reading level, age and intensity ratings so you can spot any escalation before it catches your reader off guard. For a deeper dive into how we score text difficulty vs. emotional weight separately — and why series readers especially benefit from that split — see our methodology page.
All Cycles in Science Books
Earth
Peter D. Riley
Earth
Peter D. Riley
Energy
Peter D. Riley
Energy
Peter D. Riley
Food
Peter D. Riley
Food
Peter D. Riley
Materials
Peter D. Riley
Materials
Peter D. Riley
Series Like Cycles in Science: What to Read Next
Similar reading level, content intensity and themes.
- Making Sense of Science by Peter D. Riley 7 books · Grades 6–8 · gentle content
- All-Time Worst Disasters by Susan E. Hamen 4 books · Grade 5 · mild content
- Psyched for Science by Allan B. Cobb 5 books · Grades 5–7 · gentle content
- Watts Library by Anthony D. Fredericks 9 books · Grades 6–7 · gentle to moderate content
- Untamed World by E. Melanie Watt 5 books · Grades 6–7 · gentle content
- Oceans Alive! (Brown Bear) by John Woodward 3 books · Grade 5 · gentle to moderate content
Questions about the Cycles in Science series
- What reading level is the Cycles in Science series?
- Cycles in Science books are at a grades 6–7 reading level (average grade level 6.5), and HootRated recommends the series for ages 9–12. There are 4 books in the series.
- What order should I read the Cycles in Science books?
- Series numbers aren't available for most Cycles in Science books, so HootRated lists them by publication date: Earth (1998); Energy (1998); Food (1998); Materials (1998).
- What age is the Cycles in Science series appropriate for?
- HootRated recommends Cycles in Science for ages 9–12. Content is gentle to intense (HootRated intensity 1–4 out of 5). Intensity varies from book to book, so check individual ratings in the list above.