Out of 444 students, 84.7% scored between 40 and 45 points, in the school's best performance since it started the IB programme in 2006.
Hwa Chong International School (HCIS) meanwhile scored an average of 37.2 points, a new high for the school. Its score last year was 36.8 points.
Two students from the school scored the maximum 45 points, the same as last year. This year it achieved a 100% pass rate.
The School of the Arts (SOTA) saw 80% scoring at least 35 points.
Some 90% of SOTA’s students achieved excellence in the IB Career-Related Programme (IB CP) since its conception in 2014.
The IB CP requires students to take up four core subjects, two diploma subjects, and undertake career-related study.
Twins Lim Zeharn and Lim Zeherng, 18, who specialised in visual arts, scored full marks for the IBCP.
Five students from St. Joseph's Institution (SJI) achieved perfect scores, with half the cohort scoring above 42 points.
SJI saw its largest-ever IB cohort at 187 students, scored an average of 37.7 points, up from 37.2 points last year.
The school also had more top scorers this year, with 40.6% achieving over 40 points compared to 32% previously.
All these schools are among the 24 in Singapore that offer the IB diploma.
Globally, more than 74,000 exam papers were processed in 16 languages last year, with 16,536 students graduating under the programme.
Founded in Geneva in 1968, the programme is now available in 4,783 schools in over 150 countries and territories.
IB Diploma students take six subjects and the Theory of Knowledge, a course that combines philosophy, religion and logical reasoning. They also learn a second language, write a 4,000-word essay and complete a community service project.