SOF Olympiads IMO, NSO and IEO: A Guide for Parents

6 min read · Published 7 Nov 2026

🎒 For Grade 1, Grade 2, Grade 3, Grade 4, Grade 5, Grade 6, Grade 7, Grade 8, Grade 9, Grade 10, Grade 11, Grade 12

What are the SOF Olympiads?

The Science Olympiad Foundation (SOF) runs a set of yearly olympiads for school children in Classes 1 to 12. Three of the most popular are:

• IMO, the International Mathematics Olympiad
• NSO, the science olympiad. From 2026-27, SOF lists it as the International Science Olympiad (ISO), so you may see either name on school circulars.
• IEO, the International English Olympiad

Each one is a single multiple-choice paper taken in your child's own school. Children get a chance to try questions that go a little beyond their textbook, and they see how they are doing compared with other children. Many families use the olympiads as a friendly yearly check-up on maths, science and English.

SkillStar is an independent learning app and is not connected to SOF. For official rules, dates and fees, always check sofworld.org or ask your child's school.

Who can take part, and how to register

Children from Class 1 to Class 12 can take part. There is one important thing to know: registration only happens through schools. SOF does not accept individual applications. Your child's school registers with SOF, collects the forms and fee, and chooses an exam date. If your child's school does not take part, you could ask the school whether it would consider registering.

SOF's papers are set with CBSE, ICSE/ISC and State Board syllabi in mind, so children from any board can take part.

Level 1 and Level 2

Level 1 is held in your child's school during school hours. SOF offers a few dates each year and every date has its own question paper. Each school picks one date.

Level 2 is a second round for Classes 3 to 12 only. According to SOF, children who qualify include:

• the top 5% of candidates in each class, internationally
• the top 25 rank holders from each zone in each class
• school class toppers, where at least 10 children from that class sat the exam and the topper scored at least 50%

Please check sofworld.org for the current year's rules, as details can change.

The paper pattern

All three olympiads share a common shape. The Level 1 paper lasts 60 minutes and is in English. Classes 1 to 4 answer 35 questions, and Classes 5 to 12 answer 50 questions.

IMO (Maths)

Four sections: Logical Reasoning, Mathematical Reasoning, Everyday Mathematics and the Achievers Section. In Classes 11 and 12, the Mathematical Reasoning section has a Mathematics or Applied Mathematics option.

NSO / ISO (Science)

Classes 1 to 10 have Logical Reasoning, Science and the Achievers Section. Classes 11 and 12 have Physics and Chemistry, then Mathematics or Biology, then the Achievers Section.

IEO (English)

Four sections: Word and Structure Knowledge (vocabulary and grammar), Reading, Spoken and Written Expression (everyday English such as polite requests and apologies) and the Achievers Section.

Marks

Most questions carry 1 mark. The Achievers Section has harder questions worth more: 2 marks each for Classes 1 to 4 and 3 marks each for Classes 5 to 12. SOF's published pattern does not mention negative marking.

One helpful detail: in Level 1, about 60% of questions come from the current class syllabus and about 40% from the previous class. So revising last year's work is not wasted time at all.

What makes olympiad questions different

Olympiad questions ask children to think, not just remember. A maths question might be a short real-life puzzle. A science question might describe a simple experiment and ask what happens next. An English question might ask which reply sounds most polite. Children who usually do well in school tests can find this surprising at first. That is completely normal, and it gets easier with practice.

The Logical Reasoning section in IMO and NSO covers patterns, analogies, odd one out, mirror and water images, directions, ranking, coding and decoding, and clocks and calendars. These are skills many children never meet in class, so a few puzzles a day helps a lot.

A simple preparation plan

Count backwards from the date your school has chosen. About two to three months is comfortable.

1. Start with the syllabus. SOF publishes a class-wise syllabus. Go through it together and tick what your child already knows. You can also browse the topic lists on SkillStar's IMO, NSO and IEO pages.
2. Try one sample paper without a timer. SOF shares free sample papers on its website. This shows the style of questions and where your child feels unsure.
3. Work topic by topic. Pick one or two weaker topics each week. Keep sessions short, around 20 to 30 minutes.
4. Add a few reasoning puzzles every day. Five puzzles a day for a month adds up to a lot of practice.
5. Move to full papers in the last few weeks. One timed paper a week is plenty, followed by a calm review of every mistake.
6. Keep the final days light. Rest, good sleep and a relaxed morning help more than last-minute cramming.

For IEO, reading for pleasure is wonderful preparation. Stories, children's magazines and even menus and timetables build the reading skills the paper checks.

Using past papers and mock tests on SkillStar

On SkillStar, a number of real SOF Level 1 past papers for IMO, NSO and IEO have been turned into free mock tests. They are marked instantly, so your child sees the score and the right answers straight away. There are also practice sets of short tests for every class from 1 to 12 in all three olympiads, written to follow SOF's sections and syllabus.

Other things that help:

• Daily 5: five quick questions a day from your child's exam, earning XP and keeping a gentle streak.
• Baba, our AI tutor: explains one syllabus topic at a time in simple steps, which is handy for those tricky reasoning topics.
• Progress for parents: see which tests your child has tried and which topics are worth another look.

Keeping it positive

Olympiads are meant to be a challenge, and nobody gets every question right. Praise your child for trying hard questions, for checking their work and for learning from mistakes. Avoid comparing them with classmates. Whatever the result, the real win is a child who enjoys thinking, and that lasts much longer than any certificate.