St. Patrick's Classical School was founded in 1930 when the Diocese of Meath's seminary, St. Finian's College, which had previously been the main provider of denominational education for boys locally, moved from Navan to the new diocesan capital, Mullingar in County Westmeath. The school's patron is the Roman Catholic Bishop of Meath. The school was previously located in a small architecturally distinctive building on Academy Street in the centre of the town, but in 1970 it moved to a new campus at the outskirts of the town. As its name indicated, it placed an emphasis on the teaching of the classics, Latin and Greek, rather than vocational subjects. Until the granting of "free education" by the Irish Minister for Education, Brian Lenihan, the school operated as a fee-paying school. Its education is now free. Though predominantly Roman Catholic, the school also attracts pupils from other religions and none. It particularly attracts members of the local Islamic community. Although the Roman Catholic Bishop of Meath remains the school patron, the school has long been under lay control and the last member of the clergy that was principal of the school was Fr Michael Sheerin in 1988. Following the decline in numbers of people entering the priesthood in Ireland, the school no longer has any priest on its teaching staff. On 27 November 2009, the then President of Ireland, Mary McAleese, visited the school. In March 2013, the Irish Independent Newspaper published a "lifestyle" article in which the writer described St. Patrick's Classical School as the town's "most prestigious" secondary school, which runs a waiting list of more than 200 students. In 2015, the school completed the construction of several new classrooms and an additional storey. These rooms were designed to accommodate science, woodwork, and music classes.
Notable staff
One teacher, Mr. Kevin Mallon, became a Gaelic games radio and television commentator, while another teacher, and the current school principal, Mr. Colm O'Rourke, became a member of the Meath senior Gaelic football team, before becoming one of the main panelists on Gaelic games coverage on RTÉ, Ireland's national broadcaster.
Sporting facilities at the school include two full sized Gaelic football pitches, one full size astro-turf pitch, a sports arena, a sports hall, a table tennis room, and a weights gym. Sport has been played at St. Patrick's since the foundation of the school.
Gaelic football
The Senior Gaelic football team has won the Hogan Cup three times, in 2000, 2001 and 2004. The current coaches include Mr. Colm O'Rourke. The Juvenile Football team won the North Leinster Juvenile Championship 2011 against St Mary's School in Mullingar, and the Junior team also won a "Leinster Junior A Title" in 2011/2012. In the 2012/2013 season the Senior team won the Leinster final and in the All Ireland Final in April, 2013 in lost to St. Patrick's of Maghera.
Rugby
In 2010, the Junior Rugby team won the Junior Duff Cup against Skerries Community School. In 2012, The Junior Rugby team won the Division A league and Junior Duff cup for the first time.
Basketball
The U-19's and U-16's basketball teams both made it to the north-east regional finals in 2011/2012. The U-19's won their final but were knocked out in the qualifiers for the All-Ireland. The U-16's lost their final but were able to advance to All-Ireland qualifiers but were knocked out.
Charity work
In 2014, five students from 5th year raised €1300 for the Donal Walsh #LiveLife Foundation by selling wristbands in honour of Kerry teenager Donal Walsh who had terminal cancer. In 2019 they also organised a sleep put to raise money for Focus Ireland.