The Glee star, who plays a teacher running a singing club in the musical Tv series, made an appearance at Highbury Grove School to see how the introduction of music lessons has improved pupils' academic performance.
Morrison began his visit by giving an inspirational speech during the morning assembly and praising the students for their achievements, saying, "I think music is a great thing because it helps you do math (sic) and science... and I heard about the progress that's happened in this school... since music entered your school you are now one of the top schools and I think you should give yourselves a big round of applause."
The actor later taught a music class, leading pupils in a group singing session and helping them perfect a rendition of Sir Elton John's song Mona Lisas and Mad Hatters.
He later said of his visit, "It's been fun to come over here (to the U.K.) and try to inspire these kids. In a school like this, it's quite amazing."
The school hit headlines for all the wrong reasons in April (13) when a 15-year-old boy was stabbed to death on a bus close to the entrance to the facility.