In the early days of organized education, children in the US and Europe began school at age 7, and were plunged into a world of rote memorization and strict discipline. Children of the lower class often did not attend school at all, but were given trade apprenticeships where they learned skills that would support them and their families for the rest of their lives.

Jean-Jacques Rousseau (1712-1778) wrote in his radical tract Emile about teachers being guides instead of dispensers of information, and that learning to read too soon interferes with learning how to learn, reason and be. Nearly a century after Emile was published, others had tried to incorporate these ideas into the existing school model, but no one had built a school from the ground up or applied the theories to younger children. Then, in 1840 (to mark the centennial of the invention of the printing press) when Fredrich Froebel opened The Universal German Kindergarten.
Play is the highest expression of human development in childhood for it alone is the free expression of what is in a child's soul.” – F. Froebel
Kindergarten’s innovations were many, and it is amazing to see how many have been kept and how many have been forgotten over the years:
The layout of the classroom - Kindergarten was modeled just as a garden for children. Each child not only had his or her own space in the classroom, but had a small parcel of land on which they could grow their own flowers and vegetables.

Play was important - Froebel often referred to play as the work of children. Nearly all the activities in the day started with a teacher giving the students objects or “gifts“ (see below), and with minimal instruction, letting the children explore the objects themselves.

Creativity was more important than knowledge for young children - Memorization and recitation were not a part of the curriculum at all. Even the ABCs were eschewed in favor of activities that honored art, architecture, music, and nature.

Everyone was welcome - All children no matter what race or creed were welcome at kindergarten. Froebel had tested his ideas in orphanages across Germany and had a respect for even the children who had been left behind. It would remain this way until the Third Reich came to power.

Women were teachers - because these were young children, still babies in the eyes of the academic community, women were seen as the perfect caregivers. Teaching became one of the few careers for women of the 19th and early 20th century.

The Gifts – The materials of learning were the gifts of kindergarten. Froebels’s Gifts for Kindergarten were originally packaged and sold by the Milton Bradley Company. Balls and blocks, paper and string, the Gifts were not toys, and never available for free play, but were given to children with an open ended activity in mind.
Ball on string - these were rubber balls about 1.5 inches in diameter with a cover of knitted wool. The cover extended into a 3-inch string with a small loop at the end. They were made in red, orange, yellow, green, blue and violet.

Sphere, cube and cylinder - these were packaged with 3 dowels that could be erected to hang the objects from. Children could explore geometry, art and form. They eventually became the basis for Froebel’s gravestone (see a picture of the site at http://www.geocities.com/Athens/Forum/7905/images/stein.html)

eight blocks – all one-inch cubes, forming a two inch cube (2x2x2)

eight rectangular blocks- all brick shaped blocks (2x1x1/2) forming a two-inch cube

a box of blocks - Twenty-seven one-inch cubes, three bisected and three quadrisected diagonally, forming a three-inch cube (3x3x3)

even more blocks - Twenty-seven brick-shaped blocks, three bisected longitudinally and six bisected transversely, forming a three-inch cube

Parquetry tiles – square and triangular pieces of paper that could be arranged to form pictures, patterns and abstracts

Lines – small sticks and dowels

RingsWooden, metal or paper rings of various sizes; whole circles, half circles, and quadrants

PointsBeans, lentils, or other seeds, leaves, pebbles, pieces of cardboard, paper, etc.
The Occupations – if the gifts are the materials, the occupations are the activities: molding clay, card-board work (called pricking, holes were poked in cardboard with a needle, sometimes in amazingly intricate designs), wood-carving, paper-folding, paper-cutting, parquetry (making designs with tiles), painting, interlacing, intertwining, weaving, thread games (cat’s cradle and Jacobs ladder are examples), embroidery, drawing, stringing beads, and buttons.

“The occupations furnish material for practice in certain skills, the occupations lead to to invention and give the child power.” - F. Froebel
These first kindergartens would have been revolutionary and wonderful – but what made them amazing were the people that credited kindergarten for their success. Some examples:

R. Buckminster Fuller “One of my first days in kindergarten the teacher brought us some toothpicks and semi-dried peas and told us to make structures. With my bad sight, I was used to seeing only bulks. I had no feeling at all about structural lines. The other children, who had good eyes, were familiar with houses and barns. Because I couldn’t see, I naturally had recourse to my other senses. When the teacher told us to build structures, I tried to make something that would work.”

Frank Lloyd Wright "The maple wood blocks . . . are in my fingers to this day,"
Charles Dickens visited a Kindergarten in London and after observing the children wrote: "By cutting paper, patterns are produced in the Infant Garden that would often, though the work of very little hands, be received in schools of design with acclamation." And they were – the entire Bauhaus Movement used the materials and the language of Froebel’s new method for adult artists – many of whom attended kindergarten themselves.

Children are like tiny flowers; they are varied and need care, but each is beautiful alone and glorious when seen in the community of peers.” – F. Froebel
Sources: Inventing Kindergarten by Brosterman
Froebel Web: http://www.geocities.com/Athens/Forum/7905/explore.html