Third grade science

Third grade is where science starts asking for numbers. Forces and energy, rocks and fossils, and the Sun, Earth and Moon working as a system. The content jump is smaller than the recording jump. This is the year a drawing stops being an acceptable answer.

• K
• 1st
• 2nd
• 3rd
• 4th
• 5th

What to aim for this year

By the end of third grade, a child working at grade level can usually do these.

• Plan and conduct a descriptive investigation with a measured variable, and record the results in a table.
• Predict where an object will go next from a pattern in how it has been moving.
• Describe how a force acting on an object changes its motion, and tell a balanced force from an unbalanced one.
• Identify forms of energy and trace energy moving from one place or form to another.
• Explain how rocks form and change, and name processes that break them down.
• Explain what a fossil tells us about an organism and about the environment it lived in.
• Describe the Sun, Earth and Moon system, including rotation causing day and night and the orbit taking a year.
• Explain how an inherited trait helps an organism survive where it lives.
• Give an example of a fast change to the land and a slow one, and say which is which.
• Use a data table to answer a question that nobody asked directly.

Free, and legal to use

Every one of these costs nothing. The license tag says what you may actually do with it, which is not the same question as whether it is free to read.

• USGS educational resources Free Public domain

  The Geological Survey's teaching material across geology, natural hazards, water, ecosystems, geography and the solar system, in the form of lesson plans, activities, maps, videos and animations. This is the agency that actually monitors earthquakes and volcanoes, so the maps and photographs are the real thing rather than illustrations of it.

  License: Public domain as a work of the United States government. Copy, print and adapt. Check the credit line under photographs, since a few come from partner agencies.

• NASA learning resources Free See terms

  NASA's Science Activation hub, with a searchable catalog of roughly a thousand learning resources and standards alignments already worked out. Solar system material sits at several reading levels, including printable models and imagery you can build a Sun, Earth and Moon lesson around. Orbits are hard to teach without good pictures, and these cost nothing.

  License: NASA content is generally not protected by copyright and may be copied and adapted. Third-party images hosted under permission are excluded. Insignia and endorsement limits apply.

• Smithsonian Open Access Free Public domain Not confirmed

  High-resolution fossil photographs and 3D scans of full skeletons from the National Museum of Natural History. For fossil-as-evidence work, printing a real specimen at a known scale beats any textbook drawing, and a child can lay several out and compare them.

  License: CC0 public domain dedication on items flagged Open Access, with no attribution required. Material outside that release stays restricted, so check the item record. Terms page did not load for me, so confirm.

• Exploratorium Science Snacks Free Creative Commons Not confirmed

  The force and motion builds are the cheapest route into this grade's physical science, and most run on tape, string, marbles and cardboard. Search their site for Science Snacks.

  License: Check the license. A Creative Commons NonCommercial and ShareAlike notice has appeared on these pages, but I could not confirm the current terms, so read the notice on the page you use before copying or adapting it.

• CK-12 Free Creative Commons Not confirmed

  Free digital textbooks with embedded simulations and practice questions, strongest in math and physical science. The elementary and middle school sections cover states of matter, forces and energy, and you can strip a book down to only the chapters you want. Name given without a link because the site blocked my check.

  License: Check the license. CK-12 publishes under its own stated terms rather than a plain off-the-shelf Creative Commons license, and those terms have changed over the years. Read the notice on the specific FlexBook before you adapt or redistribute anything from it.

Paid programs, honestly

Nothing here is required. These are the programs families most often ask about, with the real drawback of each one named rather than skipped.

• Mystery Science Paid $199 list, $179 in August 2026, membership through June 30, 2027.

  Good at: Third grade is where this program is strongest. The units on forces, energy and rock cycles are built around a genuine question, and the activities need household materials rather than a purchased kit.

  Drawback: Data recording is the weak point. This grade wants measured numbers written down, and the activity sheets often accept a drawing or a checked box instead. You will need to add the notebook discipline yourself.

  Suits: A parent uneasy teaching physical science who will insist on a notebook alongside.

• Building Foundations of Scientific Understanding, Volume II (Grades 3-5), Bernard J. Nebel Paid Commonly $30 to $40 paperback, less as an ebook. Publisher price not confirmed.

  Good at: Picks up the same four threads at a level that suits a third grader, and the matter and energy sequencing is the payoff for having done Volume I. One book covers three grades, which makes it the cheapest serious option on this page.

  Drawback: Still teacher-facing, still no calendar, and the checking is informal discussion rather than anything scored. There is a real risk of drift: because nothing forces pacing, families commonly reach March having done nine lessons. If you need a due date, this book will not supply one.

  Suits: A family continuing the sequence who will impose their own schedule.

• Elemental Science, Earth Science and Astronomy for the Grammar Stage Paid Around $22.50 for an ebook guide, roughly $20 to $24 each for print components, optional kit near $55, plus outside reference books. Confirm the specific title.

  Good at: Hits the space work and the earth materials work on a scheduled thirty-six-week plan, with notebooking pages an eight year old can actually fill in without a fight.

  Drawback: The required outside book list is the recurring cost and the recurring headache, and the program assumes notebooking stamina that not every eight year old has. Physical science and life science both need covering elsewhere.

  Suits: A secular family that wants the earth and space half of the year scheduled for them.

• Berean Builders, Science in the Ancient World (Jay Wile) Paid $43.00 for the textbook, confirmed on the publisher's site in August 2026.

  Good at: Runs science chronologically through history, which pairs neatly with a family already on a history cycle, and every lesson still centers on an activity. Multiple review levels let one book serve several ages at one table.

  Drawback: Young-earth creationist, and the chronological frame means topics arrive in the order history produced them rather than the order a child can absorb them. A third grader can meet a hard concept early simply because someone discovered it early.

  Suits: A young-earth Christian family running a chronological history cycle already.

Prices are approximate and change often. Check with the publisher before you buy. We describe and link to these programs; none of their material is hosted here.

What a week looks like

1. Monday. One investigation with a number in it. Roll a marble down a ramp at two heights and measure how far it travels. Table, not a drawing.
2. Tuesday. Read one USGS page on rocks or earthquakes and mark on a map where the real event happened.
3. Wednesday. Print a fossil image from the Smithsonian collection and have your child write what the animal ate and where it lived, with a reason for each guess.
4. Thursday. One force build from a Snack or from the pantry. Change one variable and record both runs.
5. Friday. Look at the week's table and answer a question you did not ask on Monday. This is the actual third grade skill.

Practice it here, free

These rooms on this site cover part of the year's work. No sign-up, and they work offline.

• know — The dinosaurs topic is the closest thing here to fossil work, and it is an introduction rather than the evidence reasoning this grade wants.
• measure — Measuring accurately, which is the skill the whole year rests on. Use it before the science, not instead of it.
• graph — Building and reading a chart from collected numbers. This is the recording half of third grade science.
• units — Choosing and converting units so a data table means something.
• patterns — Spotting and continuing a pattern, which is the reasoning move behind predicting motion.

The rest of third grade