NSO / SilverZone iOS: the last-month plan

In the last month before a science olympiad, start with one sample paper, spend two weeks on the chapters it exposes, sit a timed paper in week three and keep the final week light. SOF’s ISO (it was called NSO until this year) still has sittings on 30 October, 19 November and 3 December 2026, and SilverZone’s iOS on 19 November and 8 December 2026 — SilverZone heads its schedule “Tentative”, so confirm the date with your school.

How are SOF ISO (NSO) and SilverZone iOS different?

SOF ISO has 50 questions in 60 minutes: 10 logical reasoning, 35 science and 5 Achievers questions worth 3 marks each. SilverZone iOS has 35 questions for 100 marks, split by science theme, with 7 reasoning-and-aptitude questions and 5 Scholar’s Zone questions at the end. Both draw on the NCERT science chapters for the class.

The full side-by-side is in our post SOF ISO vs SilverZone iOS, Classes 6 to 8, and the chapter lists are on the exam guides for ISO Class 7 and iOS Class 7 (Classes 6 and 8 are linked from each).

What should each week of the last month cover?

• Week 1 — find the gaps. Sit one free science sample paper untimed. Sort every wrong answer: misread, slipped, ran out of time, or not met yet. List the not-met-yet chapters.
• Week 2 — close the biggest gaps. One chapter every two days: read the chapter note, then a science practice quiz, then the explanation on every wrong answer.
• Week 3 — practise the format. A second paper, timed. Then two days on whatever pile is now largest, and two short reasoning sessions.
• Week 4 — stay sharp, stay rested. Short quizzes on strong chapters, a re-read of notes, and no practice on the last two days.

Every week has one rest day. Twenty to forty-five minutes a day is plenty; a tired child loses marks to slips that a rested one would not make.

Can my child prepare for ISO and iOS at the same time?

Yes. Both test the same class’s NCERT science chapters, so chapter practice counts for both. What differs is the format: ISO gives more time per question, and iOS splits its marks by science theme. Practise the chapters together, and sit at least one paper in each format before the exam.

How much time should go on the reasoning section?

Two short sessions a week is enough. Reasoning is 10 of the 50 questions on ISO and 7 of the 35 on iOS, so it matters, but it should not crowd out the science chapters, which carry most of the marks on both papers.

Is the free plan enough for the last month of science practice?

Yes. OlympAI’s free plan gives 3 science practice quizzes a day of 10 questions each, every chapter note, full explanations and the free sample papers — more than this plan asks for. PRO adds timed mode and custom tests across several chapters, which some children like in week three.

Free forever, every day: up to 150 practice questions (3 quizzes × 10 questions × 5 subjects), all chapter notes, full explanations, free mock papers and 20 AI tutor messages, with no card and no time limit. OlympAI PRO is there when your child wants more: timed mode like the real exam, custom tests, Hard and Olympiad-level questions, every mock paper and 10× the AI tutor time, from ₹99 a month with no autopay. A new family’s first child also gets 14 days of PRO on us when they register.