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NGSS*2nd GradePhysical Science

2-PS1-3: Taking Apart and Building Something New

Also called NGSS 2-PS1-3 · Topic: Structure and Properties of Matter · Physical Science

All 14 2nd Grade Science Standards

The Official Wording

Make observations to construct an evidence-based account of how an object made of a small set of pieces can be disassembled and made into a new object.

Clarification statement: Examples of pieces could include blocks, building bricks, or other assorted small objects.

NGSS Lead States, 2013 · Read it on nextgenscience.org · checked October 15, 2026

What 2-PS1-3 Means in Plain English

Second graders build an object from a small set of pieces, like building bricks, take it apart, and use the same pieces to build something different. They count and record the pieces to show with evidence that nothing new was added.

Students explain what they see, not why at the particle level. The big idea, that many things are made of smaller parts, comes back in 5th grade when students learn that all matter is made of particles too small to see (5-PS1-1).

2-PS1-3 I Can Statements

  • I can take an object apart into its pieces.
  • I can build something new from the same pieces.
  • I can use a count and photos as evidence.

2-PS1-3 Worked Example

A rebuild challenge with one bag of interlocking bricks for each pair of students.

The Question

Can the bricks from a house make a boat with nothing added or left over?

Set It Up: A bag of 24 interlocking bricks for each pair, a tablet or drawing paper to record each build, and a pencil for tallies.

Bricks from house to boat
24 bricksHouseBoat
What Students Do
  1. Build a small house using all 24 bricks.House: 24 bricks
  2. Photograph or draw the house, then count the bricks by color.10 red, 8 blue, 6 green
  3. Take the house apart completely.A pile of 24 bricks
  4. Build a boat from the same bricks.A boat, a brand new shape
  5. Count the boat's bricks by color and compare with the house count.10 red, 8 blue, 6 green again
What They Find

The boat used exactly the same 24 bricks as the house, arranged in a new way.

Why it works: Many objects are made of smaller parts, and the same parts can be put together in different ways to make different things.

Common Mistakes with 2-PS1-3

Losing count

“We had 24 and now we have 22!”

Try this: Keep loose bricks in a tray and count by color before and after, so a missing piece shows up right away.

Thinking the pieces changed

“The bricks turned into a boat”

Try this: Point out that each brick is still the same brick. Only the way the bricks are arranged has changed.

Claims without evidence

“I just know it’s the same”

Try this: Back up the claim with records, like a photo of each build and a count of the pieces in both.

Where 2-PS1-3 Fits

Comes BeforeK-2-ETS1-2Sketch or build a model to show how an object's shape helps it work.
Alongside2-PS1-1Describe pieces by color, size and material, the observations used to record each build.
Comes Next5-PS1-1Model matter as made of particles too small to see, the same parts-and-whole idea at a tiny scale.5-PS1-2Measure that total weight stays the same when matter changes, more evidence that nothing is lost.

Practice 2-PS1-3

Quick Check

  1. You take apart a block tower and build a car. Are they the same blocks?
  2. How can you prove no pieces were added?
  3. Name something at home made of smaller pieces.

2-PS1-3: Other Names

2-PS1-3NGSS 2-PS1-3Building with piecesStructure and properties of matter

Official wording from NGSS Lead States. 2013. Next Generation Science Standards: For States, By States. Washington, DC: The National Academies Press. The plain-English lines and everything else on this page are EMStudio’s own explanations, written beside the official wording. They are not part of the standards.

*NGSS is a registered trademark of WestEd. Neither WestEd nor the lead states and partners that developed the Next Generation Science Standards were involved in the production of this product, and do not endorse it.