Duolingo, Clozemaster, and Other Media: Effective Tools for Supplementation of Classroom Teaching?

by Fuad Olajuwon


When measuring the ability of students to learn and process language, various factors need to be in place. Classroom instruction is an essential part of this process, as educators can observe the activities of students and calibrate lessons to fit the needs of learners. However, if teaching mostly takes place in classrooms, there is a risk students will not continue to practice and incorporate the material acquired to achieve language proficiency. It is important for students not only to practice as much as possible but also for educators to guide students through these practices. Therefore, the usage of online learning tools supports the ability to self-study, where students can continue to practice language study outside of the classroom. Before introducing some of the tools needed to facilitate learning, we must understand how to use online applications in a way that is most useful for the learner, as well as measure the effectiveness of self-study methods.

What is Self-Study?

To understand the efficacy of online language learning procedures, it is first important to understand self-study. Self-study methods can be used to learn information independently from an organized school setting. While its usage is mostly intended for independent study, it complements structured or “formal” education found in school settings (Cooper, 2003). In more traditional environments, responsibility rests among educators to create a series of plans, dates, and structures to facilitate the learning process. Self-study seeks to place more responsibility on the students, having educators attempt a more “hands-off” approach to learning ability (Armstrong, 2012).

Another common form of language study that focuses on more of a self-directed approach is self-accessed language learning (SALL). SALL practitioners create a learning environment where students have access to various materials while maintaining a high rate of autonomy. Through the usage of predetermined lesson content, educator based counseling, and online resources, students have the ability to individually configure the course curriculum (Klassen, et al. 1998). This idea is different from pure self-study, where learners are required to find material to study. Instead, SALL gives students a more traditional rubric to follow, while providing levels of individualistic autonomy. Like constructing a skyscraper, learners are given foundational tools to create learning modules tailored to their needs as long as the integrity of the course rubric remains. This educational strategy utilizes key concepts of pacing, repetition and frequency of material, time management techniques, as well as personalized feedback from educators.

What is the significance of using these tools? SALL helps to create new patterns of learning. By using predetermined content from teachers while giving students more leeway to go about studying freely, it presents a new set of skills necessary for learners to create a personalized learning plan. This model strengthens the decision-making ability of students rather than allocating most choices to educators (Cotterall, et al. 1995). Having individuals study in a way that matches their learning style while following a predetermined rubric, can lead to more productive learning results. As long as there are sets of guidelines, growth in scholastic ability, regardless of field, is very likely (Cotterall, et al. 1995). This concept holds true in language instruction as well, giving the student the liberty to acquire proficiency using any strategy that works with their distinct learning style.

Lastly, the combination of independent study imperatives with SALL methodology can lead to measured results with motivated students. Both self-study and SALL have advantages and disadvantages that can complement each other if combined in a learning environment. For example, it is necessary to mention here that some students may not adapt well to these methodologies. For example, in some cultures, traditional educational methods are considered the gold standard in terms of instruction (Scollon and Scollon,1994). Relying exclusively on self-access language learning tools may prove to be cumbersome to learners who are used to traditional classroom settings.

Autodidact Approach: Interactive Media

When students initially approach the task of learning a language, traditional forms of study are common. These methods often come from textbooks and classroom instruction. While those tools can be effective, it’s important to address other means of study outside of the classroom (i.e. the capacity to use online-based programs). With the rise of the Internet, students have the ability to study the target language without having to rely on traditional methods. This concept works great within the framework of the autodidactic approach, as motivated students create lessons to their needs. Still, this system has drawbacks, as beginner-level students may have a tough time discerning what materials to use. Hence, it is important for educators to choose materials that can be measured, while at the same time fulfilling the SALL objectives. Programs such as Duolingo have the ability to do so.

Figure 1: Example of Duolingo online classroom

Duolingo is an online language-learning module that is designed to educate students through the Internet. With over dozens of languages available to study, it has the option to learn English using a Japanese or Korean interface. This gives students and educators tools to keep the learning process fresh and new. Through online classrooms, educators have the ability to evaluate students outside of the classroom, ensuring that the assigned work gets finished promptly. While more traditional methods are effective in teaching languages, using systems that oversee the progress of students without physically setting foot in the classroom can create a higher level of learning efficacy.

One of the features of the software is the ability to conduct an online classroom. Teachers can use an assortment of different language lessons, with varying difficulty (Duolingo, 2011). Although learners are considered a part of the same online class, Duolingo provides a feeling of individuality and direct mentoring. Another strength is the diversity of material. Students have the opportunity to practice reading, writing, listening, and speaking through PC or smartphone. Most learners who commute by train or bus can make use of the software during those intervals. Educators can issue homework by individual lessons or by timeframe (i.e. 10 minutes of work). This setup works well for students, and so it can potentially prevent feelings of being overwhelmed.

This program has both advantages and disadvantages associated with the language-learning interface. The benefits of using such a system include the ability to practice daily. Duolingo keeps track of all progress made in the system and rewards users with streaks that monitor consecutive days of practice. This system works well within the learning process, as research supports the idea of absorbing small amounts of information consistently (Cepeda, et al. 2008). Referred to as the spacing effect, Duolingo encourages users to practice for less than an hour a day, while maintaining a daily regimen of language exposure. This type of regimented practice creates longer retention of material, as well as an increase in memory recall (Cepeda, et al. 2008). The program masks this idea through creating a game-like atmosphere, where users acquire points and can buy extra lessons through in-game currency. This paradigm creates an element of fun, which entices learners to keep practicing the target language.

Figure 2: Educators have the ability to issue daily assignments.

While the program contains many positive attributes that can help students, there are a few shortcomings. One flaw involves the level of difficulty. Duolingo benefits beginners and students with limited knowledge of the target language. Therefore, using this program for more advanced students isn’t feasible, except for perhaps solidifying basic foundational knowledge. More adept learners may lose interest in material that isn’t challenging enough. Translation miscues are also another factor to consider, as some of the L1 translations don’t always match. This situation causes frustration with some students, as they cannot understand the translated sentences effectively. The inability to connect with an actual language speaker is another disadvantage since the lack of live practice robs users of the ability to experience pitch, intonation, and a variety of speaking styles and forms of speech.

Another online program that is useful to students is Clozemaster. It helps learners grasp meaning and vocabulary through context, evaluating students on the ability to comprehend an array of different sentence patterns. Referred to as cloze testing, this method is used to help learners sift through language patterns and create a foundational understanding of the English lexicon (Hanzeli, 1977). This style of testing occurs when parts of sentences are removed, and students are asked to fill in the missing words or phrases.

The utilization of cloze testing requires students to understand meaning through a contextual framework, which is effective in evaluating the overall ability of L2 language knowledge (Taylor, 1953). Although Clozemaster boasts a large number of languages, this study only focuses on Japanese and Korean students looking to learn English. Practicing with sentences is the way Clozemaster works, providing the user with multiple-choice questions to help guide the learning process. More advanced students have the opportunity to write the correct answer instead, increasing the challenge factor (Clozemaster, 2017).

The program has measurable barometers, as each section is broken down into sets of ten questions. After answering, then it is the end of a section. With over 100,000 sentences, students have the ability to practice with many different sentence patterns.  Like Duolingo, this program is freeware, so it is easy for learners to register with the site and get started immediately.

Figure 3: Clozemaster interface: notice the cloze technique at work.

Clozemaster requires students to understand how to read sentences within the appropriate context. This format aims to help students to build a solid vocabulary base. However, this program also has some drawbacks which educators need to be aware of should they choose to implement it. The next section will cover some of the aspects that help to showcase the efficacy of Clozemaster and how it applies to student language proficiency, as well as some of the shortcomings associated with the program.

Clozemaster also has several advantages and disadvantages that educators need to be aware of when administering this program to students. One positive aspect of Clozemaster is how well it supplements other materials. If students are looking to get extra reading and vocabulary practice, creating the habit of sifting through the higher-level material can be essential in building up skills in proficiency. Accessing both English content as well as L1 translations helps students link together words and patterns that solidify memory retention. Furthermore, another advantage of using this software is the measurability of progress. After students complete several rounds in the program, a percentage of overall completion appears at the end of the session, allowing learners to set goals and timed tasks to motivate the learning process. This feature ensures that students have a clear idea as to how much of the program they have completed, as well as how many words in context they have retained. By having quantifiable data at hand, learners may get a sense of extra motivation.

Despite having some desirable characteristics, it’s important to recognize where the program needs to improve. Similar to other online initiatives, users should get real-world practice. Learners who rely solely on Clozemaster and other online forms may miss out on organic trial-and-error, which is an essential skill in expressing oneself adequately. While this program is a great tool for students, it isn’t as ergonomic for educators. Clozemaster is designed to be a standalone activity. Since there is no online classroom setting, teachers who want to utilize this software will have to trust that students are in fact practicing with the program, or manually take a record of progression by comparing the completion percentages between each class visit. While the task isn’t difficult, it can take up valuable class time.

Figure 4: Screenshot of the Clozemaster completion interface

Additionally, another shortcoming when using this software is the lack of clear and concise translations. While translation miscues seldom occur, some students may find some of the language content to be confusing. Nuance, syntax (whether the language is subject-prominent or topic-prominent), and grammatical structures are a few examples as to how translations may become confusing. Certain scenarios are common in online-based content, especially if the program in question teaches an array of languages. When mistranslations occur it is important to notify the students that mishaps may occur, and that it is an anomaly in the software itself, rather than an error made by the student. Consequently, this will help learners mitigate the language curriculum with less apprehension, focusing on understanding the content as a whole.

Overall, programs such as Duolingo and Clozemaster are tools that aid learner retention and proficiency. These programs benefit students by giving them frequent practice. Regardless, students need to be made aware of the shortcomings of these programs. Students can strengthen their learning by availing themselves of these tools. The next section will cover some of the components that make up these online systems, as well as the significance of using such methods in language instruction.  In addition, the paper will cover some key educational processes in place that help scholars maximize the effectiveness of interactive media.  By understanding these processes, learners and educators can craft effective strategies to ensure language ability and understanding of vocabulary.

Educational Significance

Online tools can facilitate language growth in the following ways: they help students learn outside the classroom, utilizing different learning methods, measuring the amount of material used, as well as increasing student confidence and enjoyment. Self-accessed language learning (SALL), cloze techniques, and the spaced repetition system are effective methods in creating new forms of language learning. As mentioned before, self-accessed language learning assists in creating higher learner autonomy. These are scalable objectives, as SALL promotes and encourages independence study initiatives by allowing students to be active receivers of information (Klassen, et al. 1998). Through this system, students have more control over their lesson arrangements as well as overall linguistic goals. This notion creates a sense of freedom in the learning approach, which is a more efficient way to study (Cotterall, 1995).

Not only do students have the ability to control variables within online tools like Duolingo and Clozemaster, the learning methods are also fully customizable. Within the SALL paradigm, learners can choose the level, content, and overall speed of their work, as long as educators approve it. This approach is beneficial to students since the initiative takes individual learning preferences into consideration (Gremmo & Riley, 1995; O’Malley & Chamot, 1990; Oxford, 1990; Wenden, 1991.)

Furthermore, incorporating such imperatives also increases student motivation. According to (Carter, 1999), using SALL methods helps to mitigate negative feelings towards language learning, bolsters autonomous achievement and promotes motivation. Educators need to have an understanding of SALL techniques, as well as an understanding of the levels of their students to ensure the programs work efficiently. Having a grasp of learner anxieties helps teachers create a more productive learning environment.  A combination of traditional classroom instruction and systems of interactive media is essential to learning a language. Although the role of the educator is just as important in this system, learners have to take more responsibility in the overall learning process.

Another factor is the role of spaced repetition, involving a spacing effect, which states that learning is more effective when spaced out at longer study intervals. This contrasts with binge-studying or cramming, ineffective compared to slowly memorizing material over an adequate timeframe (Greene, 1989). By spacing out learned content, students have a higher chance of recalling information. (Caple, 1996).

Duolingo uses the spaced repetition system, yielding positive results (Vesselinov, 2012; Ye, 2014). After students used the program for several weeks, Duolingo demonstrated the efficacy of implementing such a methodology, as well as maintaining motivation. This system was especially effective for beginning level learners, as the interactive software tends to focus on establishing a basic understanding of grammar and vocabulary within a language (Vesselinov, 2012). Vesselinov further reported that the effectiveness of supplementing study with online tools in preparation to take the TOEFL examination. First, students would take the Duolingo English test and determine language proficiency scores. The findings from the study indicated the following: students who used Duolingo to supplement studying for the test had significantly higher TOEIC scores than before (Ye, 2014). Therefore, spaced repetition and increased motivation were two important factors in increasing test performance.

Furthermore, such measures assist in developing the vocabulary and reading skills of students, suggesting that learners use prior knowledge to answer questions (Hanzeli, 1977). Although cloze testing is a useful tool in the development of language capability, students need to have a certain level of experience in the language. Therefore, such testing strategies work well with intermediate and advanced level students, since the pool of linguistic knowledge is much higher. Still, beginners have the ability to use this software significantly but have to rely mostly on context clues (McCray, Gareth; Brunfaut, Tineke, 2016).

Research concludes that advanced students engage in “higher-level processing,” using a broad range of contextual information and techniques to solve sets of linguistic questions (McCray, Gareth; Brunfaut, Tineke, 2016). Creating content based on mental modeling, incorporating new material, as well as implementing inference-based strategies are a few examples of how higher-level students decode language questions. This is in contrast to lower-level students, who use strategies such as word recognition, lexicology, and process of elimination to uncover solutions. This is observable by tracking the eye movements of learners. For example, lower-level students regularly glance at the word bank provided with the examination.  Secondly, lower-level students focus more on words immediately surrounding the blank, while higher-level students read the entire sentence. These observations demonstrate the different learning patterns both sets of students used to locate the answers.

Lastly, cloze testing helps formulate language patterns and sequences through context. These methods of evaluation provide learners with an increased sense of linguistic competency, enabling them to understand more obscure concepts behind language learning. Instead of teaching static parts of a language, such as memorizing grammatical tables and rules, cloze testing directs students to approach learning organically, relying on critical thinking procedures to interpret essential concepts (Hanzeli, 1977). Overall, cloze testing is an essential tool for learners to develop the necessary skills for learning a language. Furthermore, if such methods are supplemented by educators, as well as used on a consistent basis, there is a high chance for growth to occur.


As shown in this paper, a consistent and incremental program of language study is more effective than cramming. Studying both inside and outside the classroom provides the most practical way to achieve that aim. Practice outside the classroom can be accomplished through online programs that are measurable, motivating, and fun. By utilizing such programs, students have the opportunity to customize their lessons, thus addressing their personal needs and goals. This in turn incentivizes learning, creating a higher chance for students to continue practicing independently.

Online-based study materials use a series of different learning approaches to aid learners in gaining proficiency. This case study explored a few of those methods to analyze the efficiency of using such tools. Self-accessed language learning (SALL) initiatives help students to modify lessons, catering to their specific needs and creating a holistic approach to language learning. Educators have the ability to monitor the progress of students using online media and digital classroom applications. These tools give learners the ability to improve language proficiency as well as more responsibility in the learning process. This idea contrasts with traditional systems like eikaiwa, where some students have less concrete reasons to study languages (Kubota, 2011). According to Kubota, class surveys found that some students engaged in eikaiwa were content with studying once a week, while others wanted to practice more outside the classroom. Therefore, incorporating SALL could serve students wanting extra instruction. When combined with other initiatives such as the spaced-repetition system and cloze testing, online tools can play a critical role in student language development.


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Fuad Olajuwon is the Program Chair for Saitama JALT and presented this topic at the 4th Annual Saitama-Gunma MyShare. Working in Japan, he also writes about international relations, contributing to the Foreign Policy Project think-tank. When not involved in JALT activities, he is researching new methods on how to improve his teaching ability, studying East Asian politics or training in judo to one day fight in the Budokan.