K.G.6: Compose Simple Shapes into Larger Shapes
Also written as K.G.B.6 and CCSS.MATH.CONTENT.K.G.B.6 · Cluster: Analyze, compare, create, and compose shapes.
The Official Wording
Compose simple shapes to form larger shapes. For example, "Can you join these two triangles with full sides touching to make a rectangle?"
Common Core State Standards, Kindergarten, Geometry · Read it at the source · Checked October 14, 2026
What K.G.6 Means in Plain English
Kindergartners fit small shapes together to make a bigger one. Two square tiles pushed side to side make a rectangle, and two triangles from a cut square, joined along their long sides, make the square again. The rule is that whole sides touch, not just corners.
Pattern blocks are the classic material: six green triangles cover a yellow hexagon, two trapezoids do too. Children discover that the same big shape can be made several ways. In 1st grade composing extends to half-circles, quarter-circles and solids like cubes and cones (1.G.2).
K.G.6 I Can Statements
- I can put two shapes together to make a new shape.
- I can join shapes so their whole sides touch.
- I can tell which shapes I used to make a bigger one.
K.G.6 Worked Example
Two paper triangles becoming a square, with the one way of joining them that works and the ways that do not.
Here are two triangles cut from one square. Can you join them, full sides touching, to make the square again?
- Look at each triangle. Each one has a long side and two shorter sides.2 triangles, 1 long side each
- Try the short sides together first. The shape has a notch and points sticking out, so it is not a square.a shape with a gap, not it
- Turn one triangle around and slide the two long sides together until they touch along their whole length.long side against long side
- Count the new shape. Four sides, four corners, all the sides the same.4 sides, 4 corners: a square
Check it: Lay the original square tile on top. If the two triangles disappear underneath it exactly, with no paper showing, the full sides are touching.
Common Mistakes with K.G.6
Corners touching instead of sides
Two triangles meet at a single point, making a bow tie, not a square
Try this: Run a finger along the seam. It should travel the whole length of a side, not stop at a single point.
Overlapping the pieces
One triangle sits partly on top of the other to “make it fit”
Try this: Trace the target shape on paper and ask the child to fill it like a puzzle, flat, with every piece showing.
Giving up after one try
“They do not make a square.” after the short sides are tried once
Try this: Ask which side has not been tried yet, and have the child flip or turn one piece before testing the join again.
Where K.G.6 Fits
Practice K.G.6
Quick Check
- Two squares are pushed together with their whole sides touching. What shape do they make?
- You have two triangles cut from a square. Which sides should touch to make the square again?
- Dev puts six small triangles together with their sides touching and gets one big shape with six sides. What is it?