1 November 20266 min readBy Learnijoy Team
CBSE Science Challenge 2026-27: Format and 10-Day Plan
Round 1 runs in schools from 2 to 13 November 2026. Here is how it works, plus practice questions and a calm plan.
The CBSE Science Challenge 2026-27 is a free science activity for Classes 8 to 10. Round 1 is held inside schools between 2 and 13 November 2026. It is a paper of up to 60 minutes in which each prompt (CBSE calls them "stimulants"; for example a short passage, table or picture) is followed by multiple-choice questions, and it rewards both accuracy and speed. Below: the official rules from CBSE Circular Acad-67/2026 (13 October 2026), a calm 10-day plan and practice questions.
Key dates
| Stage | Dates (from the circular) |
|---|---|
| Schools register for Round 1 | 14 to 30 October 2026 |
| Round 1 paper released to schools | 2 November 2026 |
| Round 1 held in schools | 2 to 13 November 2026 |
| Schools register Round 2 students | 17 to 25 November 2026 |
| Round 2 (computer-based, run by CBSE) | One day, tentatively 30 November to 4 December 2026 |
CBSE will announce the exact Round 2 date later.
Who can take part
- Every student of Classes 8, 9 and 10 in a CBSE school can take Round 1.
- The school registers you. Students do not apply on their own. School registration for Round 1 ran from 14 to 30 October 2026, so ask your science teacher whether your school signed up and when your class will take the paper.
- There is no fee for either round.
How Round 1 works
- CBSE sends the paper; your school runs it in class.
- You get up to 60 minutes. CBSE calls it a "power and speed test": you are judged on both correct answers and time taken.
- Students with the most correct answers are considered first. If two students have the same score, the one who finished faster comes first.
- Each school then picks six students: the best two from each of Classes 8, 9 and 10 for Round 2.
Round 2 and certificates
Round 2 is computer-based and run by CBSE, only for schools that completed Round 1 and registered students. Every Round 2 participant gets an online participation certificate. The best performers get an Appreciation Certificate.
A calm 10-day practice plan
Your school may hold Round 1 on any day from 2 to 13 November (some may already have held it), so start today and shorten the plan if your date is sooner. About 30 to 40 minutes a day is enough.
| Day | Focus |
|---|---|
| 1 | Practise reading tables and graphs. Find what each row, column and axis shows. |
| 2 | Motion: speed, distance-time tables (Describing Motion Around Us) |
| 3 | Matter: mixtures and separation, atoms (Exploring Mixtures) |
| 4 | Living world: cells, tissues, life processes (Cell) |
| 5 | Force, work, energy and sound (Sound Waves) |
| 6 | Acids, bases and chemical changes (Acids, Bases and Salts) |
| 7 | Light and electricity (Electricity) |
| 8 | Timed set: 20 questions in 20 minutes |
| 9 | Go over every mistake and note why you got it wrong |
| 10 | Light revision only. Pack your pencil and sleep early. |
Class 8 students: use your own Class 8 science book for days 2 to 7 and pick the topics you have already studied. Class 10 students: add Life Processes and Heredity on day 4.
Two habits for a speed test:
- Read the question first, then the stimulus, so you know what to look for.
- If a question takes more than a minute, mark it, move on, and come back at the end.
Practice: stimulus-style questions
These are Learnijoy practice questions, not official CBSE questions. They follow the "stimulus + MCQ" style described in the circular and use core Class 9 and 10 NCERT science.
Stimulus 1. A cyclist's distance from the start is recorded every 2 seconds:
| Time (s) | 0 | 2 | 4 | 6 |
|---|---|---|---|---|
| Distance (m) | 0 | 10 | 20 | 30 |
Q1. What is the cyclist's speed? (a) 2 m/s (b) 5 m/s (c) 10 m/s (d) 30 m/s
Q2. What kind of motion is this? (a) Uniform motion (b) Speeding up (c) Slowing down (d) At rest
Stimulus 2. A student tests three liquids with pH paper. P shows pH 2, Q shows pH 7 and R shows pH 12.
Q3. Which liquid will turn red litmus blue? (a) P (b) Q (c) R (d) None of them
Q4. Which liquid could be lemon juice? (a) P (b) Q (c) R (d) Q or R
Stimulus 3. A girl stands 170 m from a tall wall and claps once. She hears the echo 1 second later.
Q5. What is the speed of sound in this case? (a) 170 m/s (b) 340 m/s (c) 85 m/s (d) 510 m/s
Stimulus 4. A potted plant is kept in the dark for two days. One leaf is then partly covered with black paper and the plant is placed in sunlight for a few hours. In an iodine test, the uncovered part turns blue-black, but the covered part does not.
Q6. What does this experiment show? (a) Leaves need water to make starch (b) Light is needed to make starch (c) Starch is made at night (d) Iodine destroys starch
Stimulus 5. A 10-ohm resistor is connected to a 5 V battery.
Q7. What current flows through it? (a) 50 A (b) 2 A (c) 0.5 A (d) 0.2 A
Answers:
- (b) 10 m every 2 s = 5 m/s.
- (a) Equal distance in equal time.
- (c) pH above 7 is basic.
- (a) Lemon juice is acidic.
- (b) Sound travels to the wall and back: 340 m in 1 s.
- (b) No light, no starch in the covered part.
- (c) I = V/R = 5/10 = 0.5 A.
Quick answers
Is there a fee? No. Both rounds are free.
Can I register myself? No. Your school registers students. Ask your science teacher.
How long is Round 1? Up to 60 minutes, with multiple-choice questions after each stimulus.
How many students go to Round 2? Up to six per school: two each from Classes 8, 9 and 10.
Treat this as a fun way to stretch your science, not a test to worry about. For more timed questions, try Learnijoy Practice.
Last updated: 1 November 2026. Source: CBSE Circular Acad-67/2026, CBSE Science Challenge 2026-27.