The Answer Key Is Already at the Photocopier
You are the subject specialist for chemistry at a district higher secondary school for girls, three days before the Grade IX first-term paper goes to press for 180 candidates in six sections. The draft was written by two teachers who disagree, and the typed answer key has already gone to the photocopier's shop. Item 12 asks candidates to identify the electrolyte from: sugar solution, copper wire, dilute hydrochloric acid, ethanol. The key marks 'copper wire' correct, with the note 'copper conducts electricity'. Item 18 is true/false: 'One mole of oxygen gas contains 6.02 x 10^23 atoms', keyed True. A full reprint costs Rs 9,000 and one working day; there is no second slot before the term break. Both teachers are senior to you, and one has already told her classes to revise from the key.
1. State precisely what is wrong with each keyed answer. Which item is a defensible question with a wrong key, and which is a factually false statement? Show the numbers.
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Item 12 - wrong key, sound item. An electrolyte conducts because it supplies mobile ions. Copper wire conducts very well, but by delocalised electrons; it is a metallic conductor, not an electrolyte. Sugar solution and ethanol are non-electrolytes. Dilute hydrochloric acid ionises in water and is the only electrolyte listed. The trap is deliberate and worth keeping: 'copper conducts electricity' is a true statement used as a false criterion. Correct key: (c).
Item 18 - the statement itself is false. One mole of O2 contains 6.02 x 10^23 molecules. Each molecule has two atoms, so the number of atoms is 2 x 6.02 x 10^23 = 1.204 x 10^24. Keying 'True' teaches an error that will cost marks in the board paper.
Consequence for the paper: Item 12 can be rescued by re-keying alone; Item 18 must either be keyed False (which then tests the molecule/atom distinction and is a better item than the original) or have 'atoms' changed to 'molecules'.
2. You have one working day and Rs 9,000. Decide what to do about both items and defend your choice against the alternatives of cancelling the items or marking everyone correct.
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Decision: retrieve the key, re-key both items, and print a single standard correction announcement that every invigilator reads aloud before the paper is distributed. No reprint of the question paper.
Why this works: neither item needs the stem rewritten if Item 18 is keyed False, so the cost is a key reprint and a one-page instruction to six invigilators - minutes, not Rs 9,000. The photocopier's shop must be told in writing to destroy the old key, because a wrong key circulating is a bigger integrity risk than the mistake itself.
Rejecting the alternatives:
- Cancel both items. The paper is presumably out of 50; removing 4 marks forces re-scaling for 180 candidates and moves every grade boundary. You are solving a 4-mark problem with a whole-cohort problem.
- Mark all candidates correct. This adds 4 marks to everyone and compresses the top of the distribution, destroying the discrimination the paper was built for. It also rewards nobody's chemistry.
- Say nothing and mark leniently later. Unfair to the six sections if leniency is applied inconsistently, and indefensible in an audit.
Fairness check: the correction must be identical in all six sections and read before the start, not after the first question, or the sections sit different papers.
3. The colleague who told her classes to revise from the key is senior to you. What do you do about the pupils who memorised 'copper wire', and what do you do about her?
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Pupils first. Those classes have rehearsed a wrong answer. The correction announcement, read before the paper in every section, neutralises the disadvantage without naming anyone: 'In Item 12, the correct option is dilute hydrochloric acid; copper conducts by electrons, not ions.' Re-keying silently would penalise exactly the pupils who trusted their teacher.
Then the colleague - privately, and about the process, not the person. The real failure is not one wrong key; it is that a key was typed and dispatched without a second reader or a check against the textbook definition. One wrong key is rarely isolated, so ask to see the rest of her draft items before they print.
System fix to propose to the head: two-person blind keying - each teacher keys the paper independently, discrepancies are resolved by argument from the textbook, and the resolved key is signed. This costs about 40 minutes per paper and would have caught both errors.
Avoid: correcting her in front of her class or in the staff room. The pupils need the correction; she needs the process; the two conversations should not be the same conversation.