The childhood homes of John Lennon and Paul McCartney in
Liverpool have been placed on a national list of protected
historic sites in England, ensuring they cannot be altered
without government approval, a quasi-governmental organization
that curates historic buildings announced Wednesday.  The
decision means the homes where the two former Beatles first
rehearsed and wrote some of their early songs, including
''Please, Please Me,'' will be protected from major changes
going forward. (A preservation group, the National Trust, has
already restored the houses to look as they did when the lads
were growing up in the 1950s.)  After his parents separated when
he was a small boy, Mr. Lennon lived from 1945 to 1963 with his
aunt and uncle in a 1930s-era duplex on Menlove Avenue known as
Mendips. Mr. McCartney lived nearby in a row house on Forthlin
Road from 1955 until the early 1960s.  The two met as teenagers
and held early practice sessions for their first group, the
Quarrymen, in these houses, and their memories