Health
Diagnostic Tests: Types, Prep, and How to Read Results
November 10, 2026
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Health
Diagnostic Tests: Types, Prep, and How to Read Results
November 10, 2026
Physics
Examples of Radioactive Decay: 15 Isotopes and Equations
November 10, 2026
Environment
Everyday Applications of Environmental Science: 9 Examples
November 10, 2026
Earth Science
14 Myths About Weather, Checked Against the Evidence
November 10, 2026
Before you buy
Books and gear for science readers, students and classrooms, with the specs and editions checked for every pick.
Best Biology Books for Self-Study
Biology books that teach without a teacher: self-teaching guides, coloring workbooks, Campbell, cell biology, biochemistry, genetics and anatomy, plus what Reddit recommends.
Best Anatomy Books for Beginners
Anatomy books that make you practice: coloring books, beginner A&P books, which Gray's to buy, atlases and picks for nursing, massage and art.
Best Chemistry Books for Self-Study
Chemistry books that teach without a teacher: self-teaching guides, problem books, general and organic textbooks and what Reddit recommends.
Free to print
Periodic tables, conversion charts and worksheets as free PDFs in US Letter and A4, with answer keys for the quizzes.
Weight Conversion Chart
Kilograms to pounds and pounds to kilograms for every body weight, plus ounces, grams and a units table.
Height Conversion Chart
Feet and inches to cm and cm to feet and inches, from 4 to 7 feet, with meters on every row.
Printable Periodic Table
Free periodic table PDFs in color, black and white, blank with a key, kids and an element list, plus a build-your-own customizer.
Fresh from the lab
Biology
Examples of Arachnids: All 11 Orders, With Real Species
Spiders are the example everyone gives, but they’re one order out of eleven. Scorpions, ticks, mites, harvestmen, camel…
November 10, 2026
Biology
Detritivores: What They Are, Examples and Why They Matter
A detritivore is an animal that eats dead organic matter, such as fallen leaves, rotting wood, dung or…
November 10, 2026
Environment
18 Facts About Light Pollution, From Stars to Sleep
Eighty-three percent of the world’s people live under a sky that artificial light has brightened. In the United…
November 10, 2026
Weather
Precipitation: Types, How It Forms, and How It’s Measured
Precipitation is any form of water, liquid or solid, that falls from clouds and reaches the ground. Rain,…
November 10, 2026
Science Basics
Formal Science Topics: A Branch-by-Branch Guide
Formal sciences study abstract systems built from axioms, definitions and rules of inference. Their claims are settled by…
November 10, 2026
Biology
Best Biology Books for Self-Study: 31 Picks, Beginner to Advanced
Biology books that teach without a teacher: self-teaching guides, coloring workbooks, Campbell and other intro textbooks, books for…
November 10, 2026
Anatomy
Best Anatomy Books for Beginners: 28 Picks From an MD-PhD
The best anatomy books for beginners, from the Kapit and Netter coloring books to Gray's Anatomy for Students…
November 10, 2026
Chemistry
Best Chemistry Books for Self-Study: 26 Picks, Beginner to Organic
Chemistry books that teach without a teacher: self-teaching guides with answers, problem books, general and organic chemistry textbooks,…
November 10, 2026
Mathematics
Best Math Books for Self Study: 28 Picks, Arithmetic to Analysis
A math professor's picks for teaching yourself math, sorted by level: refreshers for adults, algebra, precalculus, calculus, proofs,…
November 10, 2026
Why we publish
33Science is an independent publication exploring the natural world — from the chemistry of a single crystal to the life cycle of a star. Clear, curious and rigorously sourced, for readers of every background.
