Originally Posted by indigo
A high level of interaction and child-led exposure to academics can be provided outside of the context of a preschool program. For example, in a family environment, informal play group, etc.
Yes, if parents are informed and motivated:

To Help Language Skills of Children, a Study Finds, Text Their Parents With Tips
By MOTOKO RICH
New York Times
November 14, 2014

Quote
With research showing language gaps between the children of affluent parents and those from low-income families emerging at an early age, educators have puzzled over how best to reach parents and guide them to do things like read to their children and talk to them regularly.

A new study shows that mobile technology may offer a cheap and effective solution. The research, released by the National Bureau of Economic Research this month, found that preschoolers whose parents received text messages with brief tips on reading to their children or helping them sound out letters and words performed better on literacy tests than children whose parents did not receive such messages.