Kindergarten originates  from German , which literally means "garden  
So a garden of kids?  My son went to Kindergarten.
is a preschool educational approach traditionally based on playing, singing, practical activities such as drawing, and social interaction 
I remember my kiddo learning lots of songs and playing lots of games in kindergarten.  
The named was given by German Friedrich Fröbel, whose approach globally influenced early-years education.
It must be successful, because it is still going on!
Preschool
A preschool, also known as nursery school, pre-primary school, playschool or kindergarten, is an educational establishment or learning space offering early childhood education to children before they begin compulsory education at primary school. It may be publicly or privately operated, and may be subsidised from public funds.
Terminology.
Terminology varies by country. In some European countries the term "kindergarten" refers to formal education of children classified as "ISCED level 0" – with one or several years of such education being compulsory
Kindergarten
Kindergarten (, ; from German , literally meaning 'garden for the children') is a preschool educational approach based on playing, singing, practical activities such as drawing, and social interaction as part of the transition from home to school. Such institutions were originally created in the late 18th century in Bavaria and Strasbourg to serve children whose parents both worked outside home. The term was coined by the German Friedrich Fröbel, whose approach globally influenced early-years education. Today, the term is used in many countries