CISO Past Papers with Answers - Practise Online

CISO is the name some countries use for the science olympiads of Copernicus Olympiad, an organization founded in 2020 in Houston, Texas, USA. It covers two separate contests: the Copernicus Natural Science Olympiad, for students from the early primary years to Grade 12, and the Copernicus Physics and Astronomy Olympiad, for Grades 7 to 12. Each has an online Preliminary Round, and students who score at least 40% can register for an in-person Global Round.

The organizer itself does not use the acronym CISO; it is the label chosen by some country partners, including the official representative in Vietnam, which offers both science contests under one name. This guide explains the CISO levels, the CISO exam format and scoring, the rounds, and how to prepare with CISO past papers.

Overview

According to its website, Copernicus Olympiad is a brand of Eve & Ant LLC, registered in Texas, and is named after the astronomer Nicolaus Copernicus. It runs olympiads in mathematics, natural science, physics, astronomy and entrepreneurship. Its mathematics contest, known in some countries as CIMO, is the sister contest of CISO and follows the same rules for rounds, scoring and medals.

The organizer reports participants from around 50 countries; its report on the 7th edition counts 5,581 students from 30 countries in the science Preliminary Rounds. Students can register directly on the Copernicus Olympiad website or through a country representative. Papers are offered in English, Spanish, Russian and French.

Subjects

For the 2026-2027 season (the 8th edition), the organizer lists Physics and Astronomy as two separate olympiads, each for Grades 7 to 12 with the same three categories. Past papers from earlier seasons come from the combined Physics and Astronomy contest.

CISO levels and grades

There is no Grade 1 level in either contest. A secondary student can enter both Natural Science and Physics and Astronomy in the same season, as they are separate papers.

Rounds

• Preliminary Round. Every registered student takes an online qualifying exam, organized directly or with national representatives. For the 2026-2027 season, the organizer lists two Preliminary Round sittings for Natural Science and for Physics, and one for Astronomy, between October and November. Some countries call this stage the national round.
• Global Round. Students who score at least 40% in the Preliminary Round are eligible and must register separately. The Global Round is held in person; the 7th edition's science Global Round took place at Rice University in Houston. The venue is announced each season.

Students who take only the Preliminary Round can still earn medals and certificates, and the top scorer in each category is exempt from the Global Round registration fee.

CISO exam format and scoring

The format has changed over the years. The official rules for the 2026-2027 season are the same for all Copernicus science contests:

Earlier editions used different mixes of question types and time limits, so check which format a past paper follows before you time yourself.

Preliminary Round medals: 91-100% Gold, 75-90% Silver, 50-74% Bronze, 40-49% Honourable Mention. Global Round medals: Gold for the top 10%, Silver for the next 11-30%, Bronze for 31-60% and Honourable Mention for 61-75%.

When is CISO held

The science Preliminary Rounds usually take place online in October and November, and the science Global Round has recently been held in January. Partners may set their own registration deadlines and dates, so confirm with the organizer or your country representative.

How to prepare with CISO past papers

• Pick the right contest. Younger students should focus on Natural Science. From Grade 7, students who enjoy physics can add Physics and Astronomy, which needs formulas, units and calculation.
• Train with diagrams and data. Many questions are built around an experiment, a graph or a labelled diagram. Practise reading what is being measured before looking at the options.
• Revise units and orders of magnitude. In physics and astronomy questions, a wrong unit or power of ten is the most common way to pick a wrong option that looks right.
• Protect your easy marks. Every wrong multiple-choice answer costs one mark. Secure the easy and medium questions first, then return to the hard ones.
• Aim for 40%, then the medal bands. Use past papers to reach the Global Round threshold reliably before chasing gold.

On Edupiad you can take CISO past papers online with a timer, have them marked automatically, and review each question after you submit. The years and solutions available vary by category.

Frequently asked questions

What is CISO?

CISO is a name used in some countries for the Copernicus Natural Science Olympiad and the Copernicus Physics and Astronomy Olympiad. The international organizer uses the full contest names.

What grades can take CISO?

Natural Science covers Grades 3 to 12 in the current official rules (some earlier seasons included Grade 2). Physics and Astronomy covers Grades 7 to 12.

Does CISO have negative marking?

Yes. In the 2026-2027 rules, each wrong multiple-choice answer loses 1 mark. Open-ended questions in the Global Round have no penalty.

How do I qualify for the CISO Global Round?

Score at least 40% in the Preliminary Round of your contest, then complete the separate Global Round registration.

Sources

• Copernicus Natural Science Olympiad - official rules
• Copernicus Physics Olympiad - official rules
• Copernicus Astronomy Olympiad - official rules
• About Copernicus Olympiad
• Copernicus Olympiad FAQs
• Previous Olympiads - Copernicus Olympiad
• Natural Science Olympiad - International Contests Center (country partner)
• CISO 2025-2026 - Fermat Education (Vietnam partner)