An orthographic illustration of a die displaying sides 1, 3, and 2.

Die with sides 01, 03, 02

An orthographic illustration of a die displaying sides 1, 3, and 2.

An orthographic illustration of a die displaying sides 1, 5, and 3.

Die with sides 01, 05, 03

An orthographic illustration of a die displaying sides 1, 5, and 3.

An orthographic illustration of a die displaying sides 2, 1, and 3.

Die with sides 02, 01, 03

An orthographic illustration of a die displaying sides 2, 1, and 3.

An orthographic illustration of a die displaying sides 2, 3, and 6.

Die with sides 02, 03, 06

An orthographic illustration of a die displaying sides 2, 3, and 6.

An orthographic illustration of a die displaying sides 3, 1, and 5.

Die with sides 03, 01, 05

An orthographic illustration of a die displaying sides 3, 1, and 5.

An orthographic illustration of a die displaying sides 3, 2, and 1.

Die with sides 03, 02, 01

An orthographic illustration of a die displaying sides 3, 2, and 1.

An orthographic illustration of a die displaying sides 3, 5, and 6.

Die with sides 03, 05, 06

An orthographic illustration of a die displaying sides 3, 5, and 6.

An orthographic illustration of a die displaying sides 3, 6, and 2.

Die with sides 03, 06, 02

An orthographic illustration of a die displaying sides 3, 6, and 2.

An orthographic illustration of a die displaying sides 5, 3, and 1.

Die with sides 05, 03, 01

An orthographic illustration of a die displaying sides 5, 3, and 1.

An orthographic illustration of a die displaying sides 5, 6, and 3.

Die with sides 05, 06, 03

An orthographic illustration of a die displaying sides 5, 6, and 3.

An orthographic illustration of a die displaying sides 6, 2, and 3.

Die with sides 06, 02, 03

An orthographic illustration of a die displaying sides 6, 2, and 3.

An orthographic illustration of a die displaying sides 6, 3, and 5.

Die with sides 06, 03, 05

An orthographic illustration of a die displaying sides 6, 3, and 5.

Signal for the letter C, the number three, or repeat.

Signal C

Signal for the letter C, the number three, or repeat.

Probability Spinner 3

Spinner

Probability Spinner 3

Bilingual Counting Card featuring illustrations of three Sponge Divers.

Bilingual Sponge Diver Counting Card 3

Bilingual Counting Card featuring illustrations of three Sponge Divers.

English Counting Card featuring illustrations of three Sponge Divers.

English Sponge Diver Counting Card 3

English Counting Card featuring illustrations of three Sponge Divers.

Spanish Counting Card featuring illustrations of three Sponge Divers.

Spanish Sponge Diver Counting Card 3

Spanish Counting Card featuring illustrations of three Sponge Divers.

3 pointed star

Star

3 pointed star

Bilingual Counting Card featuring illustrations of three Starfishes.

Bilingual Starfish Counting Card 3

Bilingual Counting Card featuring illustrations of three Starfishes.

English Counting Card featuring illustrations of three Starfishes.

English Starfish Counting Card 3

English Counting Card featuring illustrations of three Starfishes.

Spanish Counting Card featuring illustrations of three Starfishes.

Spanish Starfish Counting Card 3

Spanish Counting Card featuring illustrations of three Starfishes.

"The stereoscope is an instrument for illustrating the phenomena of binocular vision, and for producing from two nearly similar pictures of an object the effect of a single picture with the appearance of relief and solidity that pertains to ordinary vision." — Avery, 1895

Stereoscope

"The stereoscope is an instrument for illustrating the phenomena of binocular vision, and for producing…

Three tents.

Three Tents

Three tents.

An illustration of a three person file military formation.

Three Person File Military Formation

An illustration of a three person file military formation.

Three tops.

Three Tops

Three tops.

Illustration showing three triangles. This is used to show the following theorem: If two triangles have two sides of the one equal, respectively, to two sides of the other, but the included angle of the first triangle greater than the included angle of the second, then the third side of the first is greater than the third side of the second.

Three Triangles Used to Compare Sides

Illustration showing three triangles. This is used to show the following theorem: If two triangles have…

Three violets.

Three Violets

Three violets.

An illustration of three women talking.

Three Women Talking

An illustration of three women talking.