Download clean, printable lists of the most common mistakes students make — so you can fix them before they cost marks.
Each sheet is aligned to its exam board and built from recurring student errors highlighted in examiner reports and mark schemes.
What you get
A topic-by-topic mistakes list with a “do this instead” fix and a quick self-check.
How to use it
Review before past papers, then use the quick checks to catch errors under timed conditions.
Why it works
Many marks are lost on predictable slips: rounding, sign errors, units, and misreading commands.
Coverage by topic
Preview (up to 5 per topic)
12 total rows in download
| Topic | Common mistake / misconception | Do this instead | Quick check |
|---|---|---|---|
| Microeconomics | Drawing diagrams without shading welfare areas. | IB mark schemes award marks for correctly shaded consumer surplus, producer surplus, and deadweight loss triangles. Label and shade clearly. | After drawing diagram: shade CS, PS, and DWL. Label each area. |
| Microeconomics | Confusing a price ceiling and a price floor. | Price ceiling (maximum): set BELOW equilibrium → shortage. Price floor (minimum): set ABOVE equilibrium → surplus. Wrong direction = no effect. | Ceiling below eq → shortage. Floor above eq → surplus. |
| Microeconomics | Saying a tax always raises the same revenue regardless of elasticity. | Inelastic demand → most tax revenue (small Qd fall). Elastic demand → less revenue (large Qd fall). Tax incidence also shifts with elasticity. | Inelastic demand: tax burden on consumers, more revenue. Elastic: more on producers, less revenue. |
| Microeconomics | Omitting an evaluation paragraph in long-answer questions. | IB Paper 1 Part (b) and Paper 3 require evaluation: consider assumptions, limitations, alternative perspectives, real-world context. Last body paragraph = evaluation. | Every long answer needs at least one evaluation paragraph with 'however/although/it depends...'. |
| Macroeconomics | Drawing the Keynesian AS curve as the same as the neoclassical LRAS (vertical). | Keynesian AS: horizontal (spare capacity) then upward sloping then vertical. Neoclassical: vertical LRAS at full employment. State which model you are using. | Specify: are you using Keynesian or neoclassical model? Draw accordingly. |
| Macroeconomics | Saying government spending multiplier is always greater than 1. | Multiplier = 1/(1−MPC) = 1/MPS. High MPC → large multiplier (but may cause inflation if near full employment). Low MPC → small multiplier. | Multiplier size depends on MPC/MPS. High MPC → large multiplier. BUT inflation risk if near YFE. |
| Macroeconomics | Saying deflation is always better than inflation. | Deflation can cause: debt deflation spiral, delayed consumption, business losses, banking crises. Mild inflation (2%) is typically a policy target. | Deflation: sounds good but causes: spending delays, rising real debt, recession risk. |
| International Economics | Saying free trade always benefits all countries equally. | Free trade benefits depend on comparative advantage, terms of trade, economic size, and adjustment costs. Developing countries may face challenges competing. | Evaluate: which country gains more? Are there losers (domestic industries)? Short-run vs long-run. |
| International Economics | Confusing current account and capital/financial account. | Current account: trade in goods and services, income, transfers. Capital/financial account: investment flows, portfolio flows, reserves. A CA deficit may be financed by financial account surplus. | CA deficit + financial account surplus = BoP balanced. Different parts of BoP. |
| Development | Saying economic growth always leads to development. | Growth (GDP) and development (HDI, wellbeing) can diverge. High growth may not reduce inequality or improve health/education without deliberate policy. | Growth ≠ development automatically. Redistribution, education, healthcare spending needed too. |
| Development | Using only GDP per capita to compare development. | IB requires: GDP per capita limitations (inequality, non-marketed production, environmental costs). Use HDI, Gini coefficient, multidimensional poverty index. | GDP per capita: good for income. Also cite: HDI, Gini, life expectancy, literacy for full development picture. |
| Paper Skills | Writing a definition essay instead of an evaluative one for Part (b). | Part (b) requires synthesis and evaluation, not just description. Structure: define → analyse (with diagram) → evaluate (limitations, alternatives, real-world). | Part (b): have you included a diagram, analysis, AND evaluation? All three needed. |