8ccb22b7_Math_Maturity___IAE_Pedia__Math_Cognitive_Developments
[Stage & Name] Level 2. Piagetian and Math preoperational. Age 2 to 7. [Math Cognitive Developments] 
During the preoperational stage, children begin to use symbols, such as speech. They respond to objects and events according to how they appear to be. The children are making rapid progress in receptive and generative oral language. They accommodate to the language environments (including math as a language) they spend a lot of time in, so can easily become bilingual or trilingual in such environments. During the preoperational stage, children learn some folk math and begin to develop an understanding of number line. They learn number words and to name the number of objects in a collection and how to count them, with the answer being the last number used in this counting process. A majority of children discover or learn "counting on" and counting on from the larger quantity as a way to speed up counting of two or more sets of objects. Children gain increasing proficiency (speed, correctness, and understanding) in such counting activities. In terms of nature and nurture in mathematical development, both are of considerable importance during the preoperational stage.
Math Maturity - IAE-Pedia
Math Cognitive Developments