Geometric Solids
The geometric solids are ten blue wooden shapes for children of about 3.5 to 6, from the sphere and the cube to the egg-shaped ovoid and ellipsoid. On October 5, 2026 they cost $176.75 to $202.00 at the two US sellers we found. A ball and a can start the lessons for free.
The first lesson with it is Geometric Solids. Not sure your child is ready for it? Two minutes of questions place your child on the sequence.
| Area | Sensorial |
|---|---|
| Used in | |
| From age | 3.5 to 6 years |
| Make it | Hard to make accurately |
| Buy it | About $177 to $202 (noted ) |
What the geometric solids are for
The child feels each solid with both hands, rolls it to see how it moves, and learns its name. All ten are one color, so shape is the only thing that differs. Later the child names them blindfolded and stands each one on the flat shape of its base.
Montessori's 1914 handbook lists pale blue solids: a sphere, a prism, a pyramid, a cone and a cylinder. The set of ten is the later standard. Montessori herself put the flat insets of the geometric cabinet first.
| Part | What it looks like |
|---|---|
| Rounded solids | Sphere, ovoid and ellipsoid; Nienhuis's set has three clear stands for the curved-sided ones |
| Solids with flat faces | Cube, triangular prism, rectangular prism, square-based pyramid, triangular-based pyramid |
| Solids with one curved face | Cylinder and cone |
| Base shapes | Flat figures to stand the solids on; Alison's includes five, with a wooden box |
The lessons that use the geometric solids
Geometric Solids
3.5 to 6 yearsHandling ten pale blue wooden solids, feeling each with closed eyes, rolling them to see which roll and which stand still, and learning their names.
Buying one: 4 listings checked October 5, 2026
| Seller and set | Made of | Price |
|---|---|---|
| NienhuisThe Geometric Solids (004800)Ten solids and three clear stands for the curved-sided solids. No basket. Minimum age 3. | Beech, polymer | $176.75 |
| Alison's MontessoriGeometric Solids with Bases and Planes, Premium Quality (PS15)Ten solids, five plane figures, three stands and a wooden storage box. Made in Sri Lanka. | Wood, painted blue | $202.00 |
| The Montessori RoomGeometric Solids with Plane Figures and Box (A050)Canadian store. Sold as a budget version: ten solids, five plane figures, bases and a wooden box. | Blue wood, wooden bases | $189.99 CAD |
| The Montessori RoomGAM Geometric Solids (Gm030000h)Canadian store. Ten solids with wooden bases for the three rounded ones, plus three-part cards. One left when we looked. | Solid blue wood, wooden bases | $229.99 CAD |
- Alison's set costs $25.25 more than Nienhuis's and adds the base shapes and a box. Nienhuis's has the stands but no basket.
- Montessori Outlet sold only a tray and a set of plane figures for the solids when we looked, not the solids themselves. Montessori Services had a booklet set and a basket, also without solids.
- Check that the points of the cone and pyramids are clean and that the stands hold the egg shapes still.
- The Montessori Room's two Canadian sets cost $189.99 CAD, sold as a budget version, and $229.99 CAD with three-part cards.
Making the geometric solids at home
What to gather
- A ball about 6 cm across
- A square wooden block and a long rectangular one
- A small can or a wooden dowel cut to a cylinder
- A small funnel or a party hat for the cone
- A wooden egg
- One color of paint or tape, so shape is the only difference
| Piece | Size and marking | How many |
|---|---|---|
| Cylinder | A dowel about 6 cm across, cut 6 cm long | 1 |
| Base cards | Circle, square and rectangle traced from the solids' faces | 3 |
- 1Gather solids of roughly similar size, so size doesn't give the answer away.
- 2Paint or wrap them all one color.
- 3Trace the flat faces onto card to make base shapes.
- 4Keep them in one basket, separate from toys.
Keeping a full set on the shelf
- Store the solids low. They're heavy enough to dent a floor or hurt a foot.
- Touch up chipped paint before a point splinters.
Questions parents ask about the geometric solids
What are the 10 Montessori geometric solids?
Sphere, cube, cylinder, cone, triangular prism, rectangular prism, square-based pyramid, triangular-based pyramid, ovoid and ellipsoid.
Are the geometric solids in Montessori's own books?
Yes. Her 1914 handbook lists five pale blue solids and describes rolling them and naming them with closed eyes.
Can I use household objects instead?
For a start, yes, if they're all one color. A ball and a can cover the first lesson. The bought set matters more once the child is comparing prisms and pyramids.
Before the geometric solids, make sure the work before it is solid. The geometric cabinet (plane geometric insets) lesson lists the signs that a child is ready to move on.