The acts of scribbling are just simple records of enjoyable kinesthetic activity and were not meant to visualize something. The scribbles are characterized by irregular patterns of lines and curves as shown by the sample work below.
The pre-schematic age occur between ages 4-7. Arts in this stage ranges from simple forms of circles and lines that visualize something to a clearer representation of symbols and schema of something from the environment. There is no understanding of space and figures are just placed haphazardly. The figures below are typical of an early pre-schematic stage art and a transition from scribbling stage to pre-schematic stage.
Between ages 7-9 the child's arts are a little conscious about space already. Minor details are present such as the arms and feet, and the arts are aware on the use of baseline. The schema this time is a definite way of portraying the subject but tends to exaggerate on something the child wanted to emphasize. More often objects come in groups and not just a single figure as a show of the child's social development.
The stage between ages 9-11 is characterized by expression of arts with more realistic details. The use of three-dimensional space is now apparent with perspective characteristics. Details as to sex, age, and sizes are more pronounced.