Think, McFly, Think! Get pupils thinking with the generation effect

Originally written for SecEd Magazine and published on 09 March 2023.

In the Back to the Future trilogy, whenever the oversized bully Biff Tannen demands “thinking”, he repeatedly raps his victim, the hapless George McFly, on the head with his closed fist as if he were knocking on a door, shouting, “Hello? Hello? Anybody home?!”, followed by: “Hey, think, McFly, think.”

I am sure there are better ways of getting someone to think, although I have not actually tried Tannen’s strategy with my pupils. There are clearly some teaching and learning strategies that get pupils to do this better than others.

For instance, Doug Lemov (2015) argues that we should endeavour to increase the “thinking ratio” in learning activities.

The thinking ratio denotes the amount of “cognitive work” every pupil has to do in order to fully benefit from a task in class. Low ratio activities could include teaching from the front, watching a video, or simply reading a text without any prompts, discussion or follow-up activities.

The generation effect

The generation effect, which is not dissimilar to, but not to be confused with “generative learning” (see Hanke, 2012), is one way teachers can encourage active cognitive processing, or thinking, and subsequently increase the thinking ratio.

Put simply, it refers to the idea that knowledge will be better remembered if it is generated via cues rather than simply read.

The psychologist Robert Bjork (2023) argues that tasks that get pupils to generate words rather than merely reading them can have a long-lasting impact on learning.

He gives the example of using word fragmentation, or letter stems, such as “fl____” for “flower”, as cues for retrieval of vocabulary or key terms; essentially “fl” is the cue for the target word “flower”.

Cognitive scientists have studied the impact of the generation effect in mathematics, reading comprehension and the retention of general knowledge (McNamara & Healy, 2000; Wittrock, 1989). In all of these topic areas, generation activities were seen to have a positive effect on retaining knowledge.

More recently, a meta-analysis of studies looking at generation effect activities found that the overall effect size of the activities reviewed suggests a moderate but significant impact on learning (Bertsch et al, 2007).

Nonetheless, like most ideas stemming from cognitive science, some researchers suggest the evidence for the generation effect should be approached with caution (Begg et al, 1991). Others argue that it has a limited impact if target words are new or unfamiliar (Lutz et al, 2003).

That said, the emerging consensus is that the strategy is promising but needs further examination (McCurdy et al, 2020).

Allow time to forget a little between generation tasks

Like retrieval practice, the generation effect works best if activities are spaced. As the authors of Make It Stick (Brown et al, 2014) suggest: “This process of forgetting what has been learned involves forgetting ‘retrieval cues’ or replacing those cues with new ones.”

Here, retrieval cues, such as word stems or word fragmentation (see below), are useful for retrieving knowledge from long-term memory. Moreover, when generation tasks are spaced, it is often the cue that is forgotten as opposed to the knowledge itself (Brown et al, 2014; Beale, 2020).

Using retrieval cues, or tasks that incorporate the generation effect, can arguably increase our thinking ratio and utilise more of our knowledge: “There’s virtually no limit to how much learning we can remember as long as we relate it to what we already know” (Brown et al, 2014; Beale, 2020).

In some ways, these are conceptually similar to Asembul’s “advance organisers”, which seek to expand and generate further learning by using previous learning as a “hook” (see Jones, 2022).

Basic generation tasks

Word stem completion: Pupils are given the first few letters of a word and are tasked to complete the word as quickly as possible. In sociology, my pupils often have to complete key terms at the start of lessons via word stems, such as “ano___” (anomie) that have been taught in previous lessons.

Word fragmentation completion: Word fragments include some of the letters of a previously taught word with blank spaces for missing letters. For example, in GCSE religious studies pupils should really know the five pillars of Islsm in Arabic, so I might include the following as part of a retrieval strategy prior to a written answer:

  • “s_a_a_a_” (shahadah)
  • “s_l_h” (salah)
  • “z_k_h” (zakah)
  • “s_w_” (sawm)
  • “h_j_” (hajj).

Pupils have to generate the whole word from the cued fragments.

Word pairs (or pair associates): These teach pupils how to think about the relationship between specific words. Simple classroom activities, again used as precursors to more elaborate tasks, could include generating “target” words from an associated “cue” word, for instance “heaven – ____?”, the answer being “hell”.

Pairs can include opposites or antonyms, synonyms, rhyming words or categories, such as “whale – ___________?”, the answer being “mammal”.

Importantly, this has the added benefit of allowing pupils, particularly younger learners, to see how words are used in “intelligible contexts” (Miller & Gildea, 1987).

It is also worth noting that research suggests that some pairs have a very strong forward association, from cue to target, but a weaker backward association. For example, “lamp” to “light” when reversed becomes less clear as “light” could link to all manner of responses “dark”, “heavy” etc (Koriat & Bjork, 2005). Furthermore, some word pairs are contextually non-reservable, such as “fish and chips”, and could be problematic for English as an additional language learners if reversed to “chips and fish”.

Completion tasks: Whereas a worked example, or modelled answer, explicitly instructs pupils how they should complete a task or answer, a completion task consists of a partially complete example that learners must finish. In a sense, the partially completed steps, text or diagram will act as a cue and the missing components of the example are the target to be generated.

A very basic example of a completion task is a gap or word fill which could incorporate both word stem and word fragmentations to scaffold pupils, instead of simply asking them to choose the correct word from a list.

Analysing morphographs: This strategy can improve pupils’ understanding of technical words as well as the accurate spelling of them (Essex, 2019). Pupils identify morphographs – word bases, prefixes and suffixes – as a spelling strategy to generate the correct words.

For example, in sociology my pupils are taught that “demo” means people and “ocracy” means power. In later activities, they have to analyse the meaning of terms “theocracy”, “bureaucracy”, and “technocracy” by combining terms from separate lists based on a mixture of previously taught vocabulary and “new” words that are defined.

Flashcards: This is a common strategy and one that is seen as highly beneficial to learning in comparative studies (Dunlosky, 2013). Their use allows a pupil to generate a correct answer from a cue that could incorporate any of the ideas above. Flashcards can also use visual cues, incomplete sentences, or foreign words as the cue for the target word (with the emphasis on generating the translation in the latter).

Other strategiesThere are, of course, numerous other strategies that get pupils generating target answers through a combination of prior learning and explicit, abstract or visible cues. These could include cryptic clues or questions, incomplete dual-coding, and anagrams.

Final thought

The learning benefits from self-generation have long been demonstrated. However, in the same way that academic researchers are further investigating how the process of generation works best, teachers also need to trial some of the basic ideas above in order to ascertain any long-term impact on pupils’ outcomes.

Failing that, you could always try Biff Tannen’s rapping on the head method!

Further information & resources

  • BealeDesirable difficulties, The Tony Little Centre, 2020
  • Begget al:Generating makes words memorable, but so does effective reading, Memory and Cognition (19), 1991:
  • Bertsch et al: The generation effect: A meta-analytic review, Memory and Cognition (35), 2007:
  • Bjork: Applying cognitive psychology to enhance educational practice, Bjork Learning and Forgetting Lab, UCLA (accessed 2023)
  • Brown et al: Make IStick: The science of successful learning, Harvard University Press, 2014.
  • Dunlosky et al: Improving students’ learning with effective learning techniques:Promising directions from cognitive and educational psychologyPsychological Science in the Public Interest (14), 2013
  • EssexSupporting diverse learners, Royal Society of Chemistry: 2019:
  • Hanke: Generative learningIn: Seel (ed), Encyclopedia of the Sciences of Learning. Springer2012:
  • Jones: Lesson planning: Knock-out pupils with a double hook, SecEd, 2022
  • Koriat & Bjork: Illusions of competence in monitoring one’s knowledge during studyJournal of Experimental Psychology: Learning, Memory, and Cognition, (312)2005:
  • Lemov: Teach like a champion 2.0Jossey-Bass,2015.
  • Lutz, Briggs & Cain: An examination of the value of the generation effect for learning new material, The Journal of General Psychology (130), 2003:
  • McNamara & Healy: A procedural explanation of the generation effect for simple and difficult multiplication problems and answers, Journal of Memory and Language (43,4) 2000
  • McCurdy et al: Theories of the generation effect and the impact of generation constraintPsychonomic Bulletin & Review(27), 2020:
  • Miller & Gildea: How Children learn words, Scientific American (257), 1987:
  • Wittrock: Generative processes of comprehension, Educational Psychologist (24), 1989:

Picture credit: Free SVG (used under a Creative Commons Licence)

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