Exploiting Idioms and Proverbs of Vietnamese Regions in Teaching Mathematics in Primary Schools

Mathematics and idioms, as well as proverbs, all reflect the laws of life. At the same time, primary school children may have heard idioms and proverbs before attending school. Therefore, there are many possibilities to exploit and apply idioms and proverbs in teaching mathematics in primary schools. This study aims to identify appropriate situations and apply idioms and proverbs in different regions of Vietnam to teaching mathematics. The researchers selected 1155 expressions related to mathematics from many typical pieces of research on idioms and proverbs in Vietnam. After surveying 1822 teachers three times in many provinces and cities in all 3 regions of Vietnam: the North, the Central and the South, the researchers have classified the data according to the criteria from closed to open-ended questions. The results show a prominent level of interest (level 4/5) of all teachers participating in the survey, and there is no difference in the effectiveness in the three regions, but there is a clear difference in regions in using idioms and proverbs. Particularly, identifying situations to teach geometric and quantitative knowledge, as well as probability and statistics, allows one to apply idioms and proverbs at a high level. It is concluded that if idioms and proverbs from Vietnamese regions are appropriately selected and applied in teaching mathematics in primary schools, they will contribute to improving students' mathematical ability and preserving the national cultural heritage.

Idioms and proverbs are generally used in the Vietnamese community in all three regions of the North, the Central, and the South. However, in each region and each ethnic group, there are groups of idioms and proverbs commonly used in life, along with common idioms and proverbs of Vietnam. Idioms and proverbs have been used in mathematics teaching in Vietnamese primary schools. But it seems that no research has been carried out to document these activities. This paper aims to identify situations and apply idioms and proverbs from different regions of Vietnam to the teaching of mathematics at the primary education level.

2-Literature Review
Idioms and proverbs are part of every country's national culture and are an essential part of daily life. Consequently, researchers worldwide are interested in connecting the contents of idioms and proverbs to teaching and learning at different educational levels and subjects. For example, Hayran (2017) calculated the number of proverbs and idioms in Turkish children's books taught to elementary school students and discovered that the percentage of idioms and proverbs was insufficient [14]. However, Ajoke et al. (2015) examine the use of proverbs in teaching English as a second language in Nigerian secondary schools and conclude that proverbs and idioms are a significant part of the English language and are a universal artistic expression [3]. Similar findings are also mentioned in Hinkel's (2017) research and Tamimy's (2019) observation [4,5]. Idioms and proverbs are regarded as essential socio-cultural tools for lifelong learning [2], included in HIV and AIDS messages for young people [15], or utilized to understand work ethics [16]. In addition, stories, idioms, and proverbs have been employed as cultural teaching aids to impart environmental knowledge to young people [6].
Studies on idioms, proverbs, folktales, and poems in mathematics teaching have received great attention from many researchers worldwide. First, Nichol (2022) has listed 100 English idioms that specialize in numbers that are close and friendly to the daily lives of primary students. Some idioms that are easy to understand are "Two wrongs don't make a right", "A million miles away", "As easy as one-two-three", and "Kill two birds with one stone" [17]. Furthermore, Tsarev (1998) discusses the role, meaning and particular relevance of the correct selection of proverbs, poems, and riddles in teaching mathematics in primary schools. Through the author's observation, poems, riddles, and proverbs in teaching math arouse children's positive emotions in learning mathematics and make it more colorful and exciting. For students to be more active and stimulate their exploration, the author also proposes a way for students to find proverbs related to the mathematical content they have learned and organize games related to mathematics to remember those proverbs [8]. Additionally, Raki (2022) introduces materials on mathematics-related idioms in Raki's Rad resources. These are divided into eight major topics, including (1) idioms about quantity (two is better than one; two wrongs do not lead to one right); (2) idioms about money (not worth a penny; not a penny in pocket); (3) idioms about the system (make a big change; the difference doesn't matter); (4) probability idioms (nine out of ten; one in a million); (5) idioms about time (sooner or later; on time); (6) idioms about fractions (all whole; subdivided many times); (7) idioms about position (about the starting line; direct confrontation); and (8) idioms about measurement (weighing; balancing; lightning fast) [9].
In the Vietnamese primary education context, idioms and proverbs are short, simple phrases and sentences rich in images and very meaningful. Primary school students learn idioms and proverbs in subjects such as literature and Vietnamese to see the beauty of the national language, and respect and love the original values. Moreover, idioms and proverbs are also introduced in other subjects such as Ethics to teach children towards good order and lifestyle. Or, in social sciences, they help them easily remember the rules of the surrounding natural environment and see the closeness of Vietnamese to their daily lives [18]. However, the researchers calculated the number of idioms and proverbs appearing in the textbooks of Mathematics, Vietnamese and Sciences in grades 3, 4, 5 and discovered that the Vietnamese have 175, the Sciences has 8, and Mathematics has 0. It seems that idioms and proverbs have not been officially taught in primary mathematics textbooks. Some folk games, folk songs, fairy tales and other tangible and intangible cultural heritages have been introduced in several documents on teaching mathematics in primary schools, but they have not expressed their views on how to select and use those documents. Moreover, in fairy tales, there are fictional elements, and folk songs mainly express feelings in the family and society, while idioms and proverbs are summaries of experiences from real life to bring good values to people. Therefore, it is necessary to determine the orientations for selecting and using idioms and proverbs in teaching mathematics in primary schools [18].

3-Materials and Methods
Since using idioms and proverbs in mathematics teaching is relatively new in Vietnamese primary schools, the research implemented a survey questionnaire with mathematics teachers. In quantitative research, surveys are vital tools used to collect information on individual perspectives in a large cohort [19]. There are four main advantages to using a questionnaire (Appendix I). These are efficient uses of time, provide anonymity (for the respondent), have the possibility of a high return rate, and are standardized questions [20]. In this research, primary school teachers were selected as the respondents, as they are involved in classroom activities and experienced in using idioms and proverbs in teaching. The data collection procedure for this research included three stages ( Figure 1).

Stage 1:
The researchers collected documents related to Vietnamese idioms and proverbs by surveying primary school teachers twice with five closed mathematics teaching questions (in March and July 2021).

Stage 2:
The researchers identified the criteria to categorize the idioms and proverbs related to mathematics and surveyed the teachers based on three categories.

Stage 3:
The researchers surveyed 149 teachers in different regions with five open-ended questions to identify the common and different features of using idioms and proverbs in teaching mathematics at the primary education level. Moreover, the researchers also explored the changed and unchanged factors through three times of surveying.

Figure 1. Stages of the data collection procedure
The results from closed questions provided quantitative data, while the findings from open-ended questions gave qualitative data.
Totally, 1,822 primary school teachers participated in the survey, and the sample detail is presented in Table 1.

4-1-Effectiveness of Using Idioms and Proverbs in Teaching Mathematics
The research selected 38 idioms and proverbs to test the effectiveness of using these idioms and proverbs in teaching mathematics in primary schools. The study used a 5-level Likert scale to measure, in which level 1 is Ineffective while level 5 is Very effective. Consequently, the minimum mean score for each item (idiom or proverb) is 1, while the maximum mean score is 5. Table 2 highlights the results. It can be seen that all the idioms/proverbs received a mean score of above 3.0 (out of 5.0). Eight idioms/proverbs received a mean score of above 3.40. They include Please don't leave the wasteland, Dividing into five, splitting into seven, Nine skipping work ten, Having the merit of grinding iron can make a needle, If you study, you will know, if you go, you will arrive, There is before there is after, Can count on the fingers of one hand, The more you travel, the more you learn, Two times five equals ten (It's as clear as daylight). These idioms and proverbs were evaluated effectively in teaching mathematics by the teachers.

4-2-Comparison of Mean Scores among three Regions
The effectiveness of using idioms and proverbs in teaching mathematics in primary schools in three Vietnamese regions (the North, the Central and the South) was analyzed by ANOVA test (Table 3). It can be seen that there are 9 idioms/proverbs having the Sig value of less than 0.05. These idioms/proverbs are Frog in the well, Eat less but more delicious, Having only a bow of porridge, but having to run three distances, Three dew and one sun, A relative of the 10th generation is closer than a stranger, Barrier in front, fence behind, Hair with two kinds of colours, Banana trees behind, areca trees in front, Few gifts but a lot of love. This means there is a difference in statistics among the regions for using these idioms and proverbs in mathematics teaching.

4-3-Comparison of Mean Scores among Three Locations
The effectiveness of using idioms and proverbs in teaching mathematics in primary schools in three Vietnamese locations (Mountainous, Rural and Urban) was analyzed by ANOVA test (Table 4). It can be seen that there are 26 idioms/proverbs having the Sig value of less than 0.05. This means there is a difference in statistics among the locations (mountainous areas, rural areas and urban areas) for using these idioms and proverbs in mathematics teaching.

4-4-Interest in Using Idioms and Proverbs in Teaching Mathematics in Primary Schools
The survey results show that primary school teachers were quite interested in using idioms and proverbs in teaching mathematics in their classrooms (Figure 2).

Figure 2. Teachers' interest in using idioms and proverbs in mathematics teaching
It can be seen that nearly 17% of the teachers were very interested, and 46% were interested in using idioms and proverbs in teaching mathematics. Meanwhile, only 5% of the teachers were not very interested, and 1.5% were not interested in this regard.

4-5-Methods of Using Idioms and Proverbs in Mathematics Teaching
The study also surveyed primary school teachers on how they used idioms and proverbs in teaching mathematics in their classrooms through a 5-level Likert scale, of which level 1 means Completely disagree while level 5 means Completely agree. The result is presented in Table 5. It can be seen that the teachers used idioms and proverbs in different activities to teach mathematics. They used them the most frequently to give examples (mean score = 4.0), to teach integrated, interdisciplinary topics (mean score = 3.9), to design applied exercises (mean score = 3.8), and to design advanced exercises (mean score = 3.7).

4-6-Results of Open-Ended Questions
The study used open-ended questions to ask 149 primary school teachers in different regions about their interest in using idioms and proverbs in teaching mathematics in their classrooms. The result shows that 29 teachers (19%) expressed they were very interested, 109 teachers (73%) said they were interested, while only 5 teachers said it was normal, and 5 others were not interested. The study asked teachers about the probability of using idioms and proverbs in teaching knowledge circuits of mathematics, including numbers and calculations, geometry and measurement, and probability and statistics. The result is presented in Figure 3. It can be seen that the knowledge circuits of numbers and calculations and geometry and measurement received the highest number of times, 98 and 93, respectively. This is almost twice as many times of selection of probability and statistical knowledge circuits.
Additionally, the study asked teachers about activities in which they used idioms and proverbs in the classroom. The result is highlighted in Table 6. The teachers participating in the study also pointed out the advantages and difficulties they encountered when they used idioms and proverbs in teaching mathematics in their primary education classrooms. The result is presented in Table 7. From 149 teachers, 123 indicated their suggestions to overcome the difficulties. Their recommendations are summarized in Table 8. It can be seen that teachers should pay special attention to explaining to students the meaning of idioms and proverbs related to mathematical content in specific lessons. At the same time, idioms and proverbs must be familiar and appropriate to the student's understanding of mathematics and other subjects.

5-Discussion
First of all, the current research results show that idioms and proverbs can be used in teaching mathematics in Vietnamese primary schools. Specifically, 38 idioms and proverbs in the survey received at least 3 mean scores (out of 5). The associated literature points out that teaching science can benefit from using tales, idioms, and proverbs. For example, Mutonyi (2016) argues that idioms and proverbs might assist in scaffolding children's knowledge of certain scientific topics, potentially opening up the science field to many who might not be interested in learning it [6]. Additionally, these research findings echo that of Hoang et al. (2021). [7], who categorized 1,155 Vietnamese idioms and proverbs into five mathematical competencies and recommended using them in teaching mathematics. This research indicates that primary school teachers observed the effectiveness of using idioms and proverbs in their mathematics lessons.
The ANOVA test for region reveals that the sig value of 9 idioms/proverbs is less than 0.05, which means there is a difference in statistics among the regions. These results indicate that some idioms and proverbs, when used in teaching mathematics in primary schools, need to pay attention to the characteristics of each region. There may be idioms and proverbs that are effective for students in the North but less effective in the Central and Southern regions, and vice versa. In addition to the idioms and proverbs that are common to the whole of Vietnam in the different areas or ethnic groups, teachers need to choose the most appropriate idioms and proverbs to create opportunities for students to learn mathematics and Vietnamese at the same time as well as their ethnic languages and other subjects. This finding is in line with that of McNaught et al. (2014), who observed the primary classroom practices in three different regions of China (Shanghai, Hong Kong, and Chongqing). They identified major differences in teaching methods, classroom activities, and curriculum implementation in schools in these regions [21]. Consequently, it can be seen that besides idioms and proverbs common to all three regions and ethnic groups in Vietnam, there are also very specific idioms and proverbs that are convenient for teachers to choose and apply in specific situations. With such an approach to applying idioms and proverbs to teaching mathematics in primary schools, students will feel the closeness and familiarity of idioms and proverbs with mathematical knowledge and skills. Teaching mathematics in this way creates excitement and confidence for each student, even though they are studying at the elementary level.
With over 62% of the teachers showing an interest in using idioms and proverbs in their mathematics lessons, it can be seen that primary school teachers in Vietnam found it interesting and useful to implement idioms and proverbs in their classrooms. This is an advantage for teachers to exploit idioms and proverbs in Vietnamese culture for mathematics teaching. This finding supports the work of Hoang et al. (2021), who suggested that teachers actively choose idioms and proverbs and apply them flexibly in teaching mathematics to suit the learning styles of each student and group of students in the class [7]. Idioms and proverbs can be used in different classroom activities, including teaching integrated, interdisciplinary topics, designing applied exercises, or designing applied exercises. Primary school teachers are interested in using idioms and proverbs in their mathematics classrooms because most of them are familiar with knowledge related to idioms and proverbs in the Vietnamese subject. They hope to find the relationship between idioms and proverbs with primary mathematics knowledge.
The study also shows that the implementation of idioms and proverbs was the most effective when teaching knowledge circuits of probability and statistics, geometry and measurement. This is the fundamental and compulsory knowledge in the new national general education curricula for mathematics [13]. In Vietnamese culture, these knowledge circuits are reflected through experiences and life rules that have been condensed into idioms and proverbs. The research results also show that teachers used idioms and proverbs in different lesson stages, from warm-up to assessment. However, most of the teachers used them for reviewing. This finding agrees with that of Hoang et al. (2021). [7] who found that idioms and proverbs are also effective for warm-up activities as they attract students' attention and excite them. It is recommended that primary school teachers should decide which stages to use idioms and proverbs in their mathematics lessons. Moreover, they should also select the idioms and proverbs carefully as one idiom or proverbs can be effectively used in one stage but is ineffective in another stage.
When using idioms and proverbs in teaching mathematics, primary school teachers in Vietnam met several difficulties, including their limited knowledge, experience, and teaching conditions. Consequently, they proposed several suggestions that were expected to help them use idioms and proverbs more effectively in their mathematics lessons. Many teachers wished to be trained more about using idioms and proverbs in teaching at the primary education level. Obviously, professional development for primary school teachers should receive special attention [22][23][24][25], particularly in the context of Vietnam [26]. Moreover, reference books and learning materials on the selection and implementation of idioms and proverbs in teaching mathematics at the primary education level should be developed and provided to the teachers.

6-Conclusion
The power of idioms and proverbs in drawing young learners' attention to mathematics lessons has been observed in Vietnamese primary schools. These cultural values can be used in formal mathematics classrooms to attract more children into mathematics lessons. They were stated to be effective in making connections between what primary school students have already known and how mathematics enables them to understand mathematical knowledge circuits better. Moreover, using idioms and proverbs in mathematics teaching could help children remember mathematics numbers and calculations and value the nation's culture.
Using idioms and proverbs in teaching mathematics in primary schools brings many benefits. They create positive learning environments with an experiential nature and opportunities for students to practice solving simple problems in life, which helps develop their mathematical competence. However, to implement idioms and proverbs more effectively in the classroom, primary school teachers need to choose those suitable for the knowledge circuits, topics, and content of each lesson. At the primary education level, teachers should focus on idioms and proverbs related to the knowledge circuits of geometry, measurement, probability, and statistics. Teachers should also select idioms and proverbs suitable to the teaching situation, especially the stages of discovery, application, and review in each lesson. Additionally, they should exploit idioms and proverbs typical of Vietnam's regions and ethnic groups.

7-2-Data Availability Statement
The data presented in this study are available on request from the corresponding author.

7-3-Funding
The authors received no financial support for the research, authorship, and/or publication of this article.

7-5-Informed Consent Statement
Written informed consent from the patients/participants was not required to participate in this study in accordance with the national legislation and the institutional requirements.

7-6-Conflicts of Interest
The authors declare that there is no conflict of interests regarding the publication of this manuscript. In addition, the ethical issues, including plagiarism, informed consent, misconduct, data fabrication and/or falsification, double publication and/or submission, and redundancies have been completely observed by the authors.