3. There are certain authorities who rule that the obligation to read
"Parashas Zachor" and "Parashas Porah" stems from the Torah itself
("De'oraisa") (1). Accordingly, a child (under 13 years old) should not be
called up [to read these Parashas for the congregation] (2). Similarly,
people living in outlying villages where there is no "Minyan" (ten adult
males) should go to a place [where they can hear these readings] with a
"Minyan." If this is impossible, at the very least, they should read these
passages with the proper cantillation notes.
(1) Most later authorities rule that the reading of "Parashas Porah" is a
rabbinical mitzvah, not a Biblical one (Mishna Berura 685:15).
(2) Since these readings are Biblical obligations, the reader must be
Biblically obligated himself so that the congregation can fulfill their
obligation through him. This cannot be achieved by a child under 13 years
old, because he is not Biblically obligated to perform the commandments.