Any comma before and after e.g. i.e.

There must be a comma before only:

Public schools, ie state free-of-charge schools in this country, are in crisis.

Uncountable nouns, eg bread, money and time, do not have plural forms.

Now, "ie" (id est) and "eg" (exampli gratia) may have a dot depending on the English variation. Americans write "i.e." and "e.g."