How to tell a good free study resource from a bad one

The scarce resource in studying is not material — it is attention. Any topic you search will return more free explanations, worksheets and videos than you could use. The problem is that quality varies enormously and the signals students use to judge it — production values, search ranking, confident tone — correlate poorly with whether the material will help you pass.

This guide sets out the checks worth running before you commit hours to a resource. It is also, in effect, the reasoning behind our own selection rules: everything in the OffLearn directory is published by a government body, because that constraint resolves most of these questions at once.

1. Who published it, and what do they want?

Start here, always. Find the publisher — the About page, the footer, the domain registration — and ask what the site exists to achieve. This single question filters out most bad material.

Publishers with aligned incentives want you to learn the thing. Education departments and ministries publish material to support their own curriculum. Examination authorities publish past papers because informed candidates are a policy goal. National libraries, museums, archives and public broadcasters have public-service mandates. Universities publishing open courseware are demonstrating quality. None of these gain anything from you spending longer on the page than you need to.

Publishers with misaligned incentives want something else, and the material is the means. An ad-funded site's revenue scales with pageviews, which rewards thin pages split across many clicks. A lead-generation site wants your email or a tutoring booking, so the free material is deliberately incomplete at the point where it gets useful. A site optimising purely for search traffic wants to rank, which rewards covering every topic shallowly rather than any topic well.

This is not a claim that commercial material is bad — plenty of excellent resources are commercial. It is a claim that you should know what the site wants, because it shapes what the material does.

2. Is it aligned to your curriculum?

This is where the most time gets wasted, and it is invisible unless you check. A perfectly accurate, well-explained resource can still be the wrong resource, because subject content is defined locally.

A student sitting AQA GCSE Chemistry in England and a student sitting Chemistry in a US state under NGSS are studying overlapping but genuinely different content, assessed in different formats. A resource explaining a topic beautifully at the wrong depth, or covering material your specification excludes, costs you time twice: once studying it, and once not studying what you needed.

The check is concrete: open your specification or curriculum document and see whether the resource's content maps onto it. If the resource does not name a curriculum, jurisdiction or level anywhere, it was probably written to rank in search results rather than to teach a syllabus. That is a reasonable reason to look elsewhere.

The country pages on this site exist partly for this reason — they identify which body defines the curriculum in each jurisdiction, so you know whose document to open:

3. Is it current, and does it say so?

Curricula are reformed regularly, and several of the systems described on this site are mid-reform right now. Material written for a superseded specification can be confidently, fluently wrong about what you need to know.

Look for a publication or last-updated date, and for a stated specification version. A resource that names the specification it targets is telling you something checkable. One that does not may be fine, or may predate a reform — and you cannot tell.

Be alert to the reforms specifically: England's GCSE 9–1 grading replaced A*–G, France restructured the baccalauréat away from fixed streams, Norway's LK20 rewrote every subject, Taiwan's 108 Curriculum reorganised around competencies, Singapore is replacing streaming with subject-based banding, and New Zealand has been changing NCEA. In each case there is a large stock of pre-reform material still online and still ranking well.

4. Does it show its working?

For anything factual, ask whether the resource lets you verify it. Good educational material cites its sources, distinguishes established consensus from interpretation, and is willing to say what is uncertain or contested. Poor material asserts uniformly, because hedging costs engagement.

For worked problems, the test is whether the intermediate steps are shown. A solution that jumps from question to answer is useless for learning, and it is also unfalsifiable — you cannot spot where the reasoning went wrong. Marking schemes from examination authorities are the gold standard here precisely because they allocate marks to specific steps.

For anything mathematical or scientific, spot-check one worked example fully. Errors in free worksheets are common, and one arithmetic slip in an answer key can leave you convinced you have misunderstood a method you actually understood.

5. Can you actually use it?

A resource you cannot access is worth nothing, however good. Before committing:

• Does it work on the device you have? Some official platforms assume a desktop browser or a school-managed login. Some older material is Flash-era and no longer runs at all.
• Is it usable offline? If your connection is unreliable, downloadable PDFs beat streaming platforms. Several ministries publish full textbooks as PDFs precisely for this reason.
• Is it accessible? Scanned PDFs of typed pages cannot be read by screen readers or resized usefully. Videos without captions exclude some users entirely.
• What language is it in? Much of the best national material is published only in the national language. That is a real constraint, not a deficiency.

6. What are you allowed to do with it?

"Free to read" and "free to reuse" are different permissions, and the difference matters if you are building study materials, working in a group, or a teacher preparing lessons.

Look for an explicit licence. Creative Commons licences state the terms plainly: CC BY allows reuse with attribution; CC BY-SA additionally requires derivatives carry the same licence; the NC variants exclude commercial use; ND prohibits modification. Public domain material — which includes most US federal government works — can be used freely. Crown copyright in the UK and equivalent government licences elsewhere usually permit reuse under stated conditions such as the Open Government Licence.

Absence of a licence means default copyright: you may read it, and you may not republish it. Personal study use is generally fine everywhere; redistribution is not.

Licensing summaries here are general descriptions, not legal advice; check the specific licence attached to any material you intend to reuse. Corrections welcome.