Formative vs Summative Assessment: The Difference, and How to Use Both in Grades 6–12

By Clay Shumate

Key Takeaways

• The difference is the use, not the task. Dylan Wiliam’s review is explicit that formative and summative describe the function a piece of evidence actually serves. A unit test read and acted on is doing formative work. An exit ticket that goes in a pile is not.
• A check that counts toward the grade stops telling you the truth. Students protect the score instead of showing you the confusion. That is the single most common way a school ends up with a calendar full of formative assessment and no formative information.
• The honest effect size is about 0.20, not 0.70. Kingston and Nash screened more than 300 studies and found only 13 usable, yielding a weighted mean of 0.20 — and a 2012 commentary from five assessment researchers argued even that number should not be treated as settled.
• At scale it gets smaller again. A pre-registered trial in 140 English secondary schools, roughly 25,000 pupils, found an effect of 0.09 on GCSE Attainment 8 — not significant at the 5 percent level — and it did not narrow the disadvantage gap.
• There is no research-backed ratio. What there is, is a coverage test: every standard a summative assessment will judge should have been checked while there was still time to fix it.

Ask ten teachers to explain formative vs summative assessment and you will get ten versions of the same sentence: formative is during, summative is at the end. That is close enough to be useful and wrong in the way that matters. It describes when the task happens. The distinction that actually changes anything in a classroom is about what you do with the result afterward, and most schools get that part backwards while keeping the vocabulary perfectly.

This is a definitional article, so it starts with the definitions. But the useful part is further down: the two-axis version of the distinction, the honest numbers on how much formative assessment buys you, and the gradebook question that decides whether any of it works.

What is the difference between formative and summative assessment?

Formative assessment gathers evidence while there is still time to act on it, and the teacher or student uses that evidence to change what happens next. Summative assessment measures what was learned after the learning is finished, and the result is recorded rather than acted on. Purpose separates them; timing usually follows from purpose.

Carnegie Mellon’s Eberly Center puts the purposes plainly: formative assessment exists to “monitor student learning to provide ongoing feedback” and is generally low stakes with “low or no point value,” while summative assessment exists to “evaluate student learning at the end of an instructional unit by comparing it against some standard or benchmark” and is often high stakes with a high point value. Those two sentences do more work than most professional development on the subject.

Laid out side by side, the differences line up like this.

	Formative assessment	Summative assessment
Purpose	Find out what to teach next	Record what was learned
Timing	During a unit, while there is still time	At the end of a unit, course or year
Stakes	Low or none	Usually high
Who uses the result	The teacher and the student, immediately	The gradebook, the transcript, the school, the state
What the student does next	Revises, retries, gets reteaching	Usually nothing — the work is over
Typical grades 6–12 examples	Exit ticket, mid-draft read, circulating question, project check-in, practice problem set	Unit test, final essay, presented project, end-of-course exam, state test
Gradebook treatment	Out of the grade, or very low weight	Carries the grade
What it tells you	Where the class is right now	How far the class got

Keep one thing in view while reading that table: every row describes a tendency, and the first row is the only one that defines anything. The rest follow from it most of the time and can come apart from it, which is the next section.

What is formative assessment?

Formative assessment is any practice in which evidence of student learning is elicited, interpreted, and used to make a better-founded decision about what to teach next. The defining move is the last one. Collecting evidence you never use is not formative assessment; it is paperwork.

The formulation most of the field works from is Black and Wiliam’s 2009 version, quoted in Wiliam’s own review of the definitions: practice is formative “to the extent that evidence about student achievement is elicited, interpreted, and used” by teachers, learners or peers “to make decisions about the next steps in instruction that are likely to be better, or better founded.” Note the hedge built into it — to the extent that. It is a matter of degree, not a label you apply to a worksheet.

Wiliam and Thompson’s five strategies are the practical version, and they are worth having on a wall:

1. Clarifying learning intentions and sharing criteria for success.
2. Engineering classroom discussions, activities and tasks that elicit evidence of learning.
3. Providing feedback that moves learners forward.
4. Activating students as instructional resources for one another.
5. Activating students as the owners of their own learning.

Only the second one is what most people picture when they hear the word assessment. The other four are about what surrounds the check, and they are where the work is. If you want the technique bank rather than the theory, we keep a list of formative assessment strategies that hold up in a real class period separately.

What is summative assessment?

Summative assessment evaluates learning after a unit of instruction, against a standard or benchmark, and produces a result that gets recorded. Its job is to describe accurately where a student ended up. That is a legitimate and necessary job, and it is a different job from improving the learning.

Summative assessment gets treated as the villain in a lot of assessment writing, which is silly. Students are entitled to an honest account of what they can do, families are entitled to know, and no amount of formative checking substitutes for a moment where the work is finished and judged. The problem is never that summative assessment exists. It is that in a lot of schools it is the only assessment that gets planned, and everything else is improvised around it.

A summative assessment also does not have to be a test. In project-based work the summative assessment is usually the product and the defence of it, which has its own design problems — we cover those in assessment for project-based learning.

When the summative assessment does need to be a test, it should be a fair one that you did not write at 11pm. Mid-Terms.org has 200 free printable midterms with answer keys for grades 6–12 in Social Studies, ELA, Math and Science — 20 courses, 10 midterms each — and a Form A and Form B for every course.

Is the difference the assessment itself, or what you do with the result?

It is what you do with the result. Wiliam’s review separates two distinctions that get collapsed: assessment for learning versus of learning is about the purpose a task was designed for, while formative versus summative “relates to the function it actually serves.” Design is an intention. Function is what happened.

This is the part that turns a vocabulary lesson into something you can act on. Black and colleagues put it as a threshold: assessment “becomes ‘formative assessment’ when the evidence is actually used to adapt the teaching work to meet learning needs.” Until then it is just a task. Which produces two consequences teachers run into constantly:

• A summative test can be used formatively. Read the unit test, find that two-thirds of the class missed the same standard, reteach it. That test just did formative work, grade and all.
• A tool built for formative use can function summatively. Weight the exit tickets at fifteen percent of the quarter and they are now low-stakes summative assessments that students will optimise rather than answer honestly.

There is a second axis worth keeping separate from this one, because mixing the two is the most common confusion in the whole topic. Formal and informal describe how a check is built — planned and written in advance, or improvised while circulating. Formative and summative describe what the result is for. They cross, which gives four real combinations: a planned exit ticket you sort and act on is formal and formative; a unit test that sets a grade is formal and summative; a follow-up question that changes your next sentence is informal and formative; and a teacher quietly filing a student as one of the weak ones based on an offhand answer is informal and summative, which is the box nobody names. We take that axis apart on its own in formal vs informal formative assessment; this article stays on the formative/summative one.

Does formative assessment actually raise achievement?

Yes, modestly, and the widely quoted numbers are too big. The best-known meta-analysis of the studies that could be used found a weighted mean effect of about 0.20. A large randomised trial in English secondary schools found about 0.09. Formative assessment is worth doing and it has been oversold.

Here is the honest history, because it matters for how you talk to a principal about it. Black and Wiliam’s 1998 review is the source of the effect-size range — roughly 0.4 to 0.7 — that has been repeated in professional development for twenty-five years. In 2011, Neal Kingston and Brooke Nash went looking for the studies behind it. They screened more than 300 and found 13 that reported enough information to compute an effect size, yielding 42 independent effect sizes. The median was 0.25; a random-effects model gave a weighted mean of 0.20. By subject: 0.32 in English language arts, 0.17 in mathematics, 0.09 in science. Their conclusion was that the commonly cited figure near 0.70 is not supported by the research base.

And then the contrary evidence, which deserves saying out loud. In 2012, Derek Briggs, Maria Araceli Ruiz-Primo, Erin Furtak, Lorrie Shepard and Yue Yin published a commentary arguing that the 0.20 figure should not be treated as a baseline either. Their objections were specific: the literature search was not validated or replicable; requiring studies to use the phrase “formative assessment” excluded most work published before 2000, leaving only one such study in the review; two qualifying studies were omitted while one without a control group was included; and effect sizes computed with and without pretest data were pooled as though comparable, which in one dataset moved the mean from −0.32 to −0.14 depending on method. They concluded that “considerable uncertainty remains” and that a different set of studies could produce a meaningfully higher or lower average.

So the defensible statement is not “formative assessment produces an effect of 0.20.” It is that the research base is too thin and too uneven to support any single number, and that the numbers it does support are far below what the slide decks claim.

The cleanest evidence is the newest and the least flattering. In 2021 Jake Anders and colleagues reported a pre-registered, school-level cluster-randomised trial of the Embedding Formative Assessment programme: 140 English secondary schools, 70 treatment and 70 control, roughly 25,000 pupils, two years of monthly teacher learning communities and peer observation, analysed by intention to treat on administrative data. The effect on GCSE Attainment 8 was 1.66 points, d = 0.09, with a confidence interval from −0.01 to 0.18 — not significant at the conventional 5 percent level, though significant at 10 percent. English and maths effects were about 0.05 and not significant. For pupils eligible for free school meals the effect was smaller, 0.07, so the disadvantage gap did not narrow. Pupils with low prior attainment showed larger effects, but the difference between subgroups was not statistically significant.

That is what two years of well-supported, teacher-led formative assessment work bought at scale in real schools. It is a real, positive, small effect. Anyone presenting formative assessment as the highest-leverage thing available to a secondary school is quoting 1998 and ignoring everything since.

That trial matters more than a classroom teacher might think, because what it tested is exactly what a district buys. Embedding Formative Assessment is a packaged programme — nine monthly teacher learning community workshops a year plus monthly peer observation, delivered with light-touch external support and run mostly by teachers inside their own schools. If you are being asked to approve a districtwide formative assessment initiative, 0.09 on the primary outcome and no narrowing of the disadvantage gap is the number to hold the proposal against, not 0.70.

How many formative checks should you run before a summative assessment?

No study supports a particular ratio, and anyone who gives you one is giving you a preference dressed as research. Use a coverage test instead: every standard the summative assessment will judge should have been checked at least once while there was still time to do something about it.

Ratios like 3:1 or 80/20 show up in district assessment policies and they are made up. What is defensible is the sequence, and it is easy to audit. Take the unit test you are about to give, list the standards it asks about, and for each one answer a single question: when did I last see evidence of this, and did I change anything because of it? Any standard where the answer is “the test” is a standard you are measuring rather than teaching.

1. List the standards the summative assessment will judge. Usually four to eight for a secondary unit.
2. For each one, name the check that already happened. An exit ticket, a mid-draft read, a circulating question, a practice set you actually looked at.
3. For each one, name what you changed. If nothing changed, the check was data collection, not formative assessment.
4. Fill the gaps before the test, not after it. A standard with no check gets one in the last few days of the unit, even if it is thirty seconds of circulating.
5. Then give the summative assessment and leave the reteaching time in the calendar. A summative assessment with nothing after it cannot do double duty, and double duty is free.

Should formative assessment go in the gradebook?

Keep it out, or weight it near zero. A check that counts stops being a check. Students respond to stakes by protecting the score, which means they show you their best guess rather than their actual confusion — and the confusion was the entire reason you asked.

This is the practical consequence of the function argument above, and it is where most school assessment systems quietly fail. A department decides formative assessment matters, so it gives formative work a weight to make students take it seriously. The weight converts the work into a low-stakes summative assessment. Students optimise. The teacher keeps getting clean exit tickets and keeps being surprised by the unit test. Nobody notices, because the calendar is full of things labelled formative.

Two complications worth being honest about. First, a lot of secondary students will not do ungraded work, and that is a real constraint rather than a character flaw — they are budgeting attention across seven classes. The workable answer is usually completion credit rather than accuracy credit: the work counts for having been done, not for having been right. Second, if formative work is out of the grade, the grade rests almost entirely on summative assessment, which raises the stakes of each summative task and makes the retake question unavoidable. We go through the evidence on that in whether students should be allowed to retake tests, and the broader question of what a grade should represent in what standards-based grading actually fixes.

There is a third consequence that falls on families rather than on teachers, and it is worth getting ahead of. If formative work leaves the gradebook, a parent checking the portal in week three may see two entries where they used to see fifteen, and the reasonable conclusion from the outside is that nothing is being assessed. The fix is a sentence, sent once at the start of a term: the grade reflects what your child can do at the end of a unit, the practice in between is not counted on purpose so that mistakes during it are free, and here is where you can see that practice. A policy that is defensible but unexplained still generates the phone call.

Student self-assessment runs into exactly the same split, and the research there is unusually clear about it: used formatively and ungraded it supports achievement, and used summatively it mostly teaches students to inflate. That is covered separately.

What to tell students about why it does not count

Teenagers are not confused by this, but they are suspicious of it, and with reason — they have been told before that something does not count and then watched it count. So say the actual reasoning out loud, because the reasoning is good and they can follow it: this one is not for a grade, because I need to know what you genuinely do not understand yet, and if it were graded you would sensibly show me your best guess instead. Being wrong here costs you nothing. Being wrong on Friday costs you something. So be wrong here.

That is a more respectful position than it sounds, and it is also just true. A student who understands that the ungraded check is the safe place to be wrong will use it that way. A student who suspects everything is secretly being recorded will protect themselves on every task, which is a rational response to a system that has not explained itself.

Where the formative vs summative distinction goes wrong in real schools

Four failure modes account for most of it, and none of them is a vocabulary problem. Each one is a case of the label being right and the function being wrong.

• Labelled formative, used summatively. The most common one. The task is called formative, carries a weight, and produces optimised answers instead of information.
• Formative data collected and never used. Exit tickets in a stack on the desk. The eliciting happened; the interpreting and using did not, which means no formative assessment occurred.
• No time budgeted for the response. A check that reveals a problem on Thursday is worthless if Friday is the test and Monday is the next unit. The check is not the practice. The change is the practice.
• Summative assessment treated as the finish line. The test is graded, returned, and never read by the teacher as data. A unit test is the richest formative information a secondary teacher gets all month and most of it is thrown away.

Clay’s take: the word is doing almost no work

I have sat in meetings where the phrase “formative assessment” meant a specific document that had to be uploaded by Friday. That is the state of the term in a lot of buildings. It has become a noun describing a thing you submit, when the research definition is a verb about something you do with information.

My room is a workshop — tables in groups, no rows, and I am moving between them on a stool most of the period rather than standing at the front. The best formative information I get all day is not a document. It is overhearing a group work a misconception out loud before it spreads to the table next to them, and changing what I say to the whole class ninety seconds later. None of that gets recorded anywhere. By the research definition it is textbook formative assessment, because the evidence was elicited, interpreted and used. By the district definition it does not exist, because nothing got uploaded.

That gap is worth naming, because it points at the practical takeaway. If you want more formative assessment in a secondary classroom, the lever is almost never another instrument. It is building the period so you are among the work while it is being done, and leaving enough slack in the unit that finding a problem is not an inconvenience. Everything else is documentation.

I know what the second half of that sounds like to anyone teaching to a pacing guide. If the calendar says you are on the Industrial Revolution the week of the fourth, there is no slack to leave — that is the honest situation in a lot of buildings and pretending otherwise is useless. The version that survives a pacing guide is smaller: budget one class period per unit with nothing scheduled in it, and decide what goes in it on the day, based on what the checks turned up. One period is defensible to anyone who asks, it is recoverable if the unit runs long, and it is the difference between finding a problem and being able to do something about it. If you cannot protect one period in a three-week unit, the constraint is the pacing guide, and that is a conversation to have with the person who wrote it rather than a problem to solve with better exit tickets.

And I would be careful with the numbers in either direction. The honest version — this helps a modest amount, the big figures are not supported, and the best trial at scale found 0.09 — is more useful to a teacher than the sales pitch, because it sets a realistic expectation for what changing your practice will feel like. A 0.09 effect across 140 schools is not nothing. It is also not going to be visible in your own gradebook by Christmas, and if you were promised it would be, you were misinformed.

What should you do next?

Pick the unit you are teaching now and run the coverage test above on its summative assessment. It takes about fifteen minutes and it will usually turn up one standard the test judges that nothing has checked.

1. Run the five-step coverage audit on your current unit.
2. Find out what weight formative work carries in your gradebook. If it is more than a token, that is the first thing to change, and completion credit is the usual compromise.
3. Put one block of reteaching time after your next summative assessment, before the next unit starts, so the test can do formative work too.
4. Pick two or three checks from the strategy list and run them for a fortnight rather than trying to rebuild your whole assessment system at once.

Want the fullest version of a formative check actually changing what happens next? That is Bloom’s mastery learning cycle — the check stays ungraded, the results get sorted by error rather than by score, and a second attempt is built into the plan. The evidence for it is more contested than its reputation suggests, which is covered there.

Frequently Asked Questions

Sources

• Wiliam, Dylan. “What Is Assessment for Learning?” Studies in Educational Evaluation, 2011. UCL Discovery open-access copy. The source for the function-not-instrument definition, the Black and Wiliam (2009) formulation, and the five key strategies.
• Kingston, Neal, and Brooke Nash. “Formative Assessment: A Meta-Analysis and a Call for Research.” Educational Measurement: Issues and Practice 30, no. 4 (2011). Read via the ERIC record. More than 300 studies screened, 13 usable, 42 independent effect sizes, weighted mean 0.20, median 0.25; 0.32 in English language arts, 0.17 in mathematics, 0.09 in science.
• Briggs, Derek C., Maria Araceli Ruiz-Primo, Erin Furtak, Lorrie Shepard, and Yue Yin. “Meta-Analytic Methodology and Inferences About the Efficacy of Formative Assessment.” Commentary for Educational Measurement: Issues and Practice, 2012, University of Colorado Boulder. The methodological rebuttal to the 0.20 figure.
• Anders, Jake, Francesca Foliano, Matt Bursnall, Richard Dorsett, Nathan Hudson, Johnny Runge, and Stefan Speckesser. “The Effect of Embedding Formative Assessment on Pupil Attainment.” CEPEO Working Paper 21-10, UCL, 2021. Pre-registered cluster-randomised trial, 140 English secondary schools, roughly 25,000 pupils.
• Eberly Center for Teaching Excellence, Carnegie Mellon University. “What Is the Difference Between Formative and Summative Assessment?” Accessed for the stakes-and-purpose definitions and the worked examples.