Is there negative marking in iOS?

No. SilverZone states on its iOS page that all questions are objective-type with no negative marking for a wrong answer. With 35 questions in 40 minutes, the right strategy is to attempt everything and leave nothing blank.

SilverZone Foundation · Science · Class 8

International Olympiad of Science (iOS) Class 8: syllabus, dates and exam pattern (2026–27)

Everything you need in one place — the exact NCERT chapters this paper tests, its published exam dates, the registration window, and the full marking scheme. Updated for the 2026–27 session.

Last verified against SilverZone Foundation's own site on 24 August 2026. Exam dates re-checked on 14 October 2026.

2026–27 exam dates

Date 1

14 October 2026

Date 2

19 November 2026

Date 3

8 December 2026

SilverZone publishes these under the heading "Tentative Examination Schedule for the year 2026-27" — they are the body's own dates, but SilverZone has not marked them final, so treat them as indicative until your school confirms. One inconsistency worth knowing about: the schedule lists three dates, while the iOS page itself still describes a two-date structure ("the school may opt from the two dates suggested"). Ask your coordinator which of the published dates your school has actually opted for.

SilverZone also lists an online-mode sitting of iOS on 27 December 2026, under the same 31 October 2026 registration cutoff (moved from 30 September 2026). It was added to SilverZone's own exam-date data on 11 September 2026; the dates above are its offline sittings.

Registration: SilverZone publishes one registration cutoff covering every paper it runs, iOS included: 31 October 2026, on the same schedule it heads "Tentative Examination Schedule." It was 30 September 2026 until SilverZone moved it: on 1 October 2026 the body's own exam-date endpoint still returned 30 September 2026 on all 34 of its records, and when we re-read it on 14 October 2026 every one returned 31 October 2026, with no notice of the change on the site. That is the second time this season SilverZone has replaced its cutoff only after the earlier date had gone by: the endpoint returned 31 August 2026 on every read from 18 August to 1 September 2026, and 30 September 2026 from 2 September. So treat 31 October as SilverZone's current date rather than a settled one, in either direction. If your school has not registered, ask your coordinator to confirm with SilverZone, at info@silverzone.org, which sitting of iOS an entry made now would be for. Registration is through participating schools by default, so the cutoff binds the school rather than the family. SilverZone also runs an individual registration form at r.silverzone.org; which papers it offers, and what closing date applies to it, we have not been able to confirm.

Free — deadline calendar

The deadline is set by your school, not by you

Most parents find the exam date and assume they have until then. The registration window closes long before it, and for some papers it has already started closing. Here is how it actually works.

Your school registers your child and your school picks which of the 2–3 dates the class sits. The family does not choose.
For SOF papers, registrations must reach SOF exactly 30 days before that chosen date — and once the school has chosen, the date cannot be changed.
Most bodies register through the school. These do not have to: CREST (online, no published cutoff), Unified Council — directly for NSTSE itself at ₹350 against ₹150 through a school, and on three online sittings, NSTSE-Online, UIMO-Online and UIEO-Online, at ₹354 each including GST — Indian Talent Olympiad on its individual online route (its own later dates — Slot 1 closes 30 October), and Humming Bird (online, ₹150 a subject, no published cutoff — its two dates are picked as you register). CREST is the simplest of them. SilverZone also runs an individual registration form alongside its default school route; which papers it offers we have not been able to confirm.

Closing next

SOF IEO (English) — if your school picks 17 November 2026
Registrations must reach SOF by 18 October 2026
SOF ISO (Science) — if your school picks 19 November 2026
Registrations must reach SOF by 20 October 2026
Indian Talent Olympiad (ITO) — School route — Set B (extended from 10 October)
Registration closes 22 October 2026
SOF IHO (Hindi) — if your school picks 23 November 2026
Registrations must reach SOF by 24 October 2026
SOF IMO (Maths) — if your school picks 26 November 2026
Registrations must reach SOF by 27 October 2026

Get the full calendar on WhatsApp

Or read the full calendar on the site — no sign-up

Every deadline in this box was re-read against the exam body's own website on or after 14 October 2026. Each table carries its own source link and its own date. Bodies do move dates, so check against the body's own site before you act on one.

Exam pattern

How the iOS paper is structured

Section	Questions	Marks per question	Section total
Food — Crop Production, Microorganisms	4	2.5	10
How Stuff Works — Force and Pressure, Friction, Light, Sound, Chemical Effects of Electric Current	8	2.5	20
Living World — Reproduction in Animals, Reaching the Age of Adolescence, Conservation of Plants and Animals	6	2.5	15
Materials — Coal and Petroleum, Combustion and Flame	3	2.5	7.5
Natural Phenomena — Some Natural Phenomena	2	2.5	5
Reasoning and Aptitude	7	3	21
Scholar's Zone	5	4.3	21.5
Total	35 questions	—	100 marks · 40 minutes

Three things worth planning around. First, reasoning and the Scholar's Zone together are 42.5 of the 100 marks — the same split as the Class 6 paper — so a shade under half of this exam is not the science chapters at all, and 12 of the 35 questions carry the marks of roughly 17. Second, "How Stuff Works" is the biggest science block at 20 marks and it is the widest: five old-NCERT chapters spanning forces, friction, light, sound and the effects of electric current, which is more ground than any single Curiosity chapter covers. Third, 35 questions in 40 minutes is about 69 seconds a question — the same clock SilverZone sets its Class 6 candidates, on a syllabus that has grown considerably.

SilverZone publishes no current-year/previous-year split for iOS the way SOF does for IMO and ISO, so nothing is claimed here. The class-wise topic table is the whole of what the body publishes about what this paper contains.

Syllabus

Science syllabus mapped to NCERT Curiosity (Class 8, 2026-27)

Ch 2. The Invisible Living World: Beyond Our Naked Eye

Olympiad syllabus label: Food — Microorganisms: Friend and Foe; also Cell — Structure and Functions

Ch 3. Health: The Ultimate Treasure

Olympiad syllabus label: Living World — Reaching the Age of Adolescence (adolescent wellbeing, diet, immunisation); Microorganisms — diseases

Ch 4. Electricity: Magnetic and Heating Effects

Olympiad syllabus label: How Stuff Works — Chemical, Magnetic and Heating Effects of Electric Current (incl. electroplating and electrolysis)

Ch 5. Exploring Forces

Olympiad syllabus label: How Stuff Works — Force and Pressure; Friction

Ch 6. Pressure, Winds, Storms and Cyclones

Olympiad syllabus label: How Stuff Works — Force and Pressure (the pressure half); Wind, Storms and Cyclones

Ch 10. Light: Mirrors and Lenses

Olympiad syllabus label: How Stuff Works — Light: reflection, refraction, the human eye

Ch 11. Keeping Time with the Skies

Olympiad syllabus label: Natural Phenomena — Stars and the Solar System; Some Natural Phenomena (the astronomy half)

Ch 12. How Nature Works in Harmony

Olympiad syllabus label: Living World — Conservation of Plants and Animals; Ecosystems

Ch 13. Our Home: Earth, A Unique Life Sustaining Planet

Olympiad syllabus label: Natural Phenomena — atmosphere, greenhouse effect, the ozone layer (olympiad general-awareness scope)

SilverZone names thirteen chapters for Class 8 iOS, in the old NCERT's names. Nine of them land on a chapter of the 2026-27 Curiosity book, above. The other four are the part a parent should read before September, and they are four different stories rather than one. Crop Production, Reproduction in Animals and the lightning half of Some Natural Phenomena are all out of the Class 8 book but are covered in our own material, in the curator taxonomy's Extra Topics bucket, which exists precisely because olympiad bodies still set the pre-2023 syllabus. Combustion and Flame moved down to Class 7, where it is a single topic inside Physical and Chemical Changes, and Coal and Petroleum moved down to Class 6, where it lives inside one Natural Resources topic — both are covered, thinly, and a year or two before the child sits this paper. Sound is the one to actually plan for: it is not in the Class 8 book, it has no Extra Topics row, and searching every grade sheet finds it only at Class 9. So a Class 8 child sitting iOS can be asked about pitch, echo and wave properties that neither Curiosity nor our own Class 8 material covers, and no Class 8 teacher is going to reach it before December. Better known in August than in the hall. Two smaller notes: the Scholar's Zone names no topics on any SilverZone table, at any class, so nothing about its content is published by anyone; and Curiosity has three chemistry chapters — Particulate Nature of Matter, Elements and Compounds, and Solutions — that SilverZone's Class 8 iOS list does not name at all, so strong school performance there earns nothing on this particular paper.

Try it yourself

Today's science question

Practice

Practice in the iOS format

OlympAI has not published a practice paper for this exam yet. When one is ready, this page is where it will appear — nothing to sign up for and no phone number to hand over.

See what is on this paper

Frequently asked questions

SilverZone publishes one cutoff covering every paper it runs, not one per exam, and its school-route date is now 31 October 2026. It was 30 September 2026 until SilverZone moved it: the body's own exam-date endpoint still carried 30 September on 1 October, and returned 31 October 2026 on every record when we re-read it on 14 October. SilverZone has now moved this cutoff twice without notice, from 31 August 2026 to 30 September and then to 31 October, each time only after the old date had gone by, so treat the current date as the body's, not as settled. If your school has not registered, ask SilverZone at info@silverzone.org which sitting an entry would be for. Registration is through the school by default; SilverZone also runs an individual registration form at r.silverzone.org whose paper list we have not been able to confirm.

Yes, four of the thirteen it names. Three of them — Crop Production, Reproduction in Animals and lightning and static charge — are old Class 8 NCERT chapters that the 2026-27 book no longer carries, and they are the reason our own material keeps an olympiad-scope bucket outside the book. Combustion and Flame is now a Class 7 topic and Coal and Petroleum a Class 6 one, so a Class 8 child has met both, earlier and briefly. Sound is the real gap: it sits in Class 9 now, and nothing in the Class 8 year covers it.

iOS is 35 questions in 40 minutes for 100 marks; SOF ISO is 50 questions in 60 minutes for 60 marks. The deeper difference is the weighting: iOS gives reasoning and its Scholar's Zone 42.5 of its 100 marks, while ISO's Logical Reasoning and Achievers sections are 25 of 60. They also close on different clocks — SilverZone on a single date covering every paper (31 October 2026 as of our 14 October re-read, which SilverZone has moved twice this season without notice: off 31 August on 2 September, then off 30 September), SOF at exactly 30 days before whichever date your school picks. Preparing for one does not automatically prepare a child for the other.

Five questions at 4.3 marks each — 21.5 of the 100 marks, and the highest per-question value on the paper by a wide margin. SilverZone publishes no topic list for it on any class table, so nobody outside the body knows what it contains beyond the level its name implies. The reasonable assumption is depth on the same Class 8 science rather than extra chapters, which is how the Class 6 paper behaves.

Possibly, and it is worth one question before you rule it out. SilverZone's main route is the school, but it also runs a public individual registration form at r.silverzone.org, which its own page labels "for individual registrations only. This is not a school registration link." Which papers that form offers, we have not been able to confirm, so ask SilverZone whether it covers iOS before relying on it. If your school does not run it, four other bodies do take a family directly: CREST, Unified Council for its online sittings, Indian Talent Olympiad on its individual online route, and Humming Bird. For science specifically, all four of them run a paper, so this is one subject where the direct route is genuinely open.

Still choosing

Every olympiad a Class 8 child can sit in 2026–27

All the papers at this class, grouped by whether your school has to enter your child or you can register directly — with each body's own dates and cutoffs.

Related guides

Other olympiad syllabus guides

SilverZone Foundation · Class 6

iOS Class 6 — science syllabus, dates and pattern

SilverZone Foundation · Class 7

iOS Class 7 — science syllabus, dates and pattern

Indian Talent Olympiad (ITO) · Class 8

ITO-E Class 8 — english syllabus, dates and pattern

Indian Talent Olympiad (ITO) · Class 8

ITO-M Class 8 — maths syllabus, dates and pattern

Keep reading

Guides that answer the next question

SOF ISO vs SilverZone iOS: which science olympiad to pick

Two science olympiads whose registration dates both pointed at 30 September 2026, until SilverZone moved its own to 31 October. One of those dates is published and the other is worked out from a rule, and the two papers reward opposite habits. Here is the side-by-side for Classes 6, 7 and 8, and what to do if your school offers neither.

Which olympiad should my Class 8 child take?

The Class 8 paper list is the same 25 papers offered at Class 6 and Class 7. What changes is that the bodies stop agreeing on what Class 8 means — one paper we mapped chapter by chapter is roughly half last year’s book. The routes, the dates and the syllabus catch, read off each body on 8 September 2026.

Or see every 2026-27 exam date and registration cutoff in one table, or browse all the papers we cover.

Practice these exact chapters, free

3 practice quizzes a day in each subject free, 10 olympiad-pattern questions each, and 5 with your choice of length and difficulty on OlympAI PRO — for Class 8 science, generated from the same NCERT chapters above and written to the shape of the real olympiad papers, then automatically checked before they can be served, the hardest ones re-solved by a second model that has to agree.

Start free