Coun Joyce Pritchard, the new mayor, had approached the school personally as her children used to attend St Paul's.
The 29-strong choir, led by Mrs France and Mrs Wadsworth, sang beautifully, including a rousing rendition of 'Power in Me'.
They also enjoyed the tradition and pomp of the ceremony, asking many interesting questions about democracy and how the mayor was elected.
Coun Pritchard, who lives in Brookhouse, became a Liberal Democrat councillor in 1999 and was deputy mayor when Coun Janie Kirkman was mayor in 2006-07.
She had a break from the council from 2011 to 2019.
Coun Pritchard, who is chairman of the council business committee, is a trustee of Lancaster Almshouses.
She also represents the council on the Crook o’Lune and Forest of Bowland advisory committees.