CBSE 10th Exams 2025: A science teacher’s guide to avoiding common mistakes
CBSE 10th Exams 2025: I have learned one thing for sure: how we approach studying can make a huge difference, especially in subjects like science.
CBSE 10th Exams 2025: As a science teacher with the experience of studying at IIT Roorkee, I have learned one thing for sure: how we approach studying can make a huge difference, especially in subjects like science. On this teaching journey, I found some common mistakes that many students make while writing the answers in the science exam. I have highlighted these mistakes in this article and shared some simple but effective tips that can help you prepare better for exams.
Before moving to the common mistakes and tips, let’s see the chapter-wise weightage of the science exam:
Based on the chapter-wise marks weightage, we can divide the chapters into three categories: Highest-weightage, moderate-weightage and smaller-weightage.
● Highest-weightage
○ The chapters like “Light” and “Metals and non-metals” have the highest weightage in the exam. Focus on understanding concepts, formulas, and practice-related problems in these chapters
○ The chapters “Life process” and “Heredity and Evolution” are also important, and they carry 9 and 7 marks, respectively
● Moderate-weightage
○ “Chemical Reactions and Equations”, “Carbon and its Compounds”, “Control and Coordination”, “magnetic effect of electric current” and “Electricity” contribute 6 marks each. These are moderately weighted and should be given adequate time in preparation
● Smaller-weightage
○ Smaller-weightage chapters such as “Acids, Bases and Salts”, “How Do Organisms Reproduce?” and “The Human Eye and the Colourful World”. But still the student cannot neglect smaller chapters as they can contribute to your total score
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Common mistakes and effective tips
Reading and Understanding Questions
While reading the questions, read calmly and properly, not in a hurry. Avoid rushing while reading the questions.
MCQs Guidance
● For MCQs, first read the question without looking at the options, try to guess your answers and then check your guess with the options.
● To write the answers to MCQs on the answer sheet, it is essential to write (a), (b), etc. For example, write “Ans. 2. (a) 0.895 A” not just (a).
Writing Chemical reactions
● In science, reactions are very important. In many questions, we have to write the reactions. If the question is not directly asked, we still have to write.
● While writing any reactions, mention the physical states of each chemical in brackets, whether they are reactants or products.
● The reaction should be completely balanced.
● If a colour change is involved in the chemical reaction, then mention the reactant’s and product’s colour in brackets, just below the corresponding chemicals. See the example below.
Underlining Important keywords/information
Underlining the important keywords to highlight the main answers is very important, but underlining the whole sentences must be avoided, as this can distract from the key concepts you are trying to highlight.
Diagrams and Labelling
● To draw any diagram, especially in Biology, make sure that your diagram is neat and all the parts of the diagram are visible and clear. For that, always use a pencil to draw the diagram.
● The diagram should be perfect and well-labelled. Write all the labels on the right side of your answer sheet, and all the labels should correspond correctly to the parts of the diagram.
Ray Diagrams in Physics
● In ray diagrams of Physics, all the rays should be straight and have arrows to indicate their directions.
● Many times, I found that the student forgot to label the object and image. However, labelling the object and image with the letters AB and A’B’, respectively, is essential.
● Always use a ruler and compass while making any ray diagram.
Solving Numerical Problems
● Numerical problems from topics like light, electricity, magnetic effects of current, and other chapters come in the exam. So, solving them correctly with all the steps is essential.
● Start by writing down the information given in the question. Then, write the full formula, substitute the given values, and solve for the unknown.
● Once you’ve calculated your answer, highlight it by underlining it or drawing a box around it.
● It’s also essential to include the unit of measurement with your answer. Remember that the refractive index is unitless, so it doesn’t require a unit.
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Timeline for February month:
For CBSE Class 10 Board exams, NCERT is the key to success. In the last month before the exam, give your time to the highest-weightage chapters. Involve them in daily revisions. Solve one sample paper daily with three hours of constraint time. In the last week before the exam, don’t learn new topics, only revise the old topics that you have covered earlier and give little time to mental health i.e., take a rest to keep your mind fresh for the exam.
At the end of this article, I must say that adequate exam preparation is not just about studying harder but also more intelligent. To improve your exam performance, just do the following things: Avoid these common mistakes and manage your time.
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"Success does not consist in never making mistakes but in never making the same one a second time." – George Bernard Shaw
(Author Amit Sharma is OCFP Faculty, Malad West Campus, Orchids The International School, Mumbai)
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