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The purpose of the study is to evaluate how prospective mathematics teachers (PMTs) modify tasks ... more The purpose of the study is to evaluate how prospective mathematics teachers (PMTs) modify tasks to facilitate students' learning of pattern generalization through the use of their mathematical knowledge for teaching. Case study, which is a type of qualitative research method, was used to determine the mathematical characteristics that PMTs use when modifying a mathematical task. The knowledge from which PMTs draw to modify the task has also been outlined. Accordingly, data were collected from PMTs' task modifications and reflection reports. When PMTs worked on two or more forms of modification, as compared to just using one type of modification, they modified tasks more effectively and comprehensively. The PMTs who make condition modifications need to utilize specialized content knowledge through the use of models or tables. They aimed to help middle school students understand using these modifications, and thus they also utilized their knowledge of content and students. They also used their knowledge of content and teaching, especially while making modifications to questions and context. Task modification activities can be used to help prospective teachers notice the mathematical and pedagogical affordances and limitations offered by tasks.

Trakya eğitim dergisi, Sep 30, 2019

Ogretmen adaylarinin cebirsel dusunme ile ilgili hem kendi bilgilerini hem de ogrenciler hakkinda... more Ogretmen adaylarinin cebirsel dusunme ile ilgili hem kendi bilgilerini hem de ogrenciler hakkinda bilgilerini ortaya koymak, kavramsal bilgiye sahip olan ogretmenler yetistirmek icin ilk asama sayilabilir. Bu amacla bu calismada, ortaokul matematik ogretmeni adaylarinin oruntu genellemesi hakkindaki konu alan ve pedagojik alan bilgileri incelenmistir. Nitel arastirma tasarimi kapsaminda, 26 ogretmen adayina sabit degisen sekil oruntusu problemi ve bu problemle iliskili olarak acik uclu sorular sorulmustur. Elde edilen veriler, Ball, Thames ve Phelps (2008) tarafindan gelistirilen “Ogretmek icin Matematiksel Bilgi (OMB)” modeli kullanilarak icerik analizi ile incelenmistir. Bulgular, ogretmen adaylarinin tumunun oruntuyu cebirsel olarak dogru genelleyebildiklerini ortaya koymustur. Cogunun genellemeye ulasirken sayisal akil yurutme kullandigi tespit edilmistir. Ogretmen adaylarinin, ogrencilerin problem cozme konusundaki bilgilerinin, genellikle kendi cozum yontemlerine dayandigi gorulmustur. Ogretmen adaylarinin, ogrencilerin yasayabilecegi zorluk ve kavram yanilgilarina yonelik tahminleri oldukca sinirlidir. Dolayisiyla bunlari gidermek icin yaptiklari oneriler de yetersiz kalmistir. Bulgulara dayanarak, ogretmen adaylarini yetistirmeye yonelik oneriler yapilmistir.

İlköğretim online, Sep 15, 2020

Examining the knowledge of teachers in practice may shed light on understanding how students lear... more Examining the knowledge of teachers in practice may shed light on understanding how students learn and finding out why they have difficulty in learning. This paper focused on teachers' knowledge of pattern generalization in instruction with the consideration of students' generalization strategies in planning. The multiple-case study design was used for this study to compare and contrast two middle school mathematics teachers’ lesson planning and instruction. Lesson plans, pre-observation interviews, observations and post-observation interviews were used as the data collection tools. The data were analyzed by using the Mathematical Knowledge for Teaching (MKT) model. The findings showed that the two teachers used numerical reasoning in all representations, but they had difficulties in using figural reasoning. They generally used the tabular representation effectively to underlie the relationship of generalization. While one of the teachers defined the pattern concept correctly and always emphasized analyzing the relationship between the position number and the term, the other teacher defined the pattern concept partially correctly, and her inadequate explanations of functional thinking caused some misunderstandings of students about generalization. It was also observed that the students’ lack of knowledge about algebraic expressions prevented them from obtaining a general rule. Through the cases of these two teachers, it was noted that teachers need to have a good conceptual mathematical understanding and also knowledge of students’ thinking to design effective lessons.

Journal for the Education of the Gifted, Feb 7, 2021

Mathematically gifted students have a high potential for understanding and thinking through mathe... more Mathematically gifted students have a high potential for understanding and thinking through mathematical relations and connections between mathematical concepts. Currently, it is thought that generalizing patterns algebraically can serve to provide challenges and opportunities that match their potential. This article focuses on a mathematically gifted student’s use of generalization strategies to identify linear and nonlinear patterns in the context of a matchstick problem. Data were collected from a 10th-grade gifted student’s problem-solving process in a qualitative research design. It was observed that the gifted student’s ways of generalizing the linear and nonlinear patterns were different. In a generalization process, the student used figural reasoning in the linear pattern and numerical reasoning in the nonlinear patterns. It was noted that the student explored using Gauss’s approach in structuring the general rules of nonlinear patterns. Accordingly, aside from assisting their more gifted students, mathematics teachers may want to consider ways to introduce Gaussian thinking to the benefit of all their students.

The examination of teacher knowledge in practice can shed light to understand how students learn ... more The examination of teacher knowledge in practice can shed light to understand how students learn and find out why they have difficulty in learning. This paper will focus on teachers' knowledge of pattern generalization in instruction with planning. The multiple-case study design was used for this study to compare and contrast the two middle school teachers’ lesson planning and instruction. Lesson plans, pre-observation interviews, observations, and post-observation interviews were used as data collection tools. Data were analyzed by using the Mathematical Knowledge for Teaching (MKT) model. The findings showed that the two teachers used numerical reasoning in all representations and they could not have the knowledge of figural reasoning. The teachers' inadequate explanations of functional thinking caused some misunderstandings about generalization. Through the cases of these two teachers, it was observed that teachers need to have a good conceptual mathematical understanding...

Kastamonu Eğitim Dergisi, 2019

Bu araştırma, ilköğretim matematik öğretmen adaylarının pedagojik deneyimler içeren Matematik Tar... more Bu araştırma, ilköğretim matematik öğretmen adaylarının pedagojik deneyimler içeren Matematik Tarihi dersi öncesinde ve sonrasında matematik tarihi bilmenin gerekliliği konusunda ve kendi sahip oldukları matematik tarihi bilgileriyle ilgili algılarının neler olduğunu ve bu algılarda nasıl değişimler yaşandığını keşfetmeyi amaçlamıştır. Araştırma, ilköğretim matematik öğretmenliği programının son sınıfında öğrenim gören 32 öğretmen adayı ile gerçekleştirilmiştir. Çalışmada veriler, ders öncesi ve ders sonrası açık uçlu sorulara verilen yazılı cevaplar, öğretmen adaylarının hazırladıkları ders planları, araştırmacı notları ve derslerde yapılan sınıf tartışmaları aracılığıyla elde edilmiştir. Araştırma sonuçları, öğretmen adaylarının bir matematik öğretmenin (i) genel kültür ve saygınlık kazanmak, (ii) konu alan bilgilerini güçlendirmek, (iii) öğretim sürecini güçlendirmek ve (iv) öğrencileri matematiğe karşı duyuşsal olarak desteklemek için matematik tarihi bilmeleri gerektiği düşüncelerine sahip olduklarını göstermiştir. Pedagojik deneyimler içeren Matematik Tarihi dersi sonrasında bu düşüncelerdeki eğilimlerde ders öncesine göre belli değişimlerin olduğu görülmüştür. Diğer taraftan, araştırma sonuçları öğretmen adaylarının ders öncesinde kendi matematik tarihi bilgilerini çoğunlukla yüzeysel ve orta derece olarak tanıladıklarını göstermiştir. Ders sonrasında kendi bilgileriyle ilgili algılarında dört temel değişim ortaya çıkmıştır: (i) yüzeyselden-orta dereceye; (ii) orta dereceden-orta dereceye; (iii) orta dereceden-derine ve (iv) derinden-orta dereceye olarak gruplandırılmıştır. Elde edilen sonuçlar, öğretmen adaylarının Matematik Tarihi ile ilgili pedagojik deneyimler (ör. ders kitaplarında matematik tarihinin analizi, matematik tarihi içerikli ders planı tasarlama) yaşadıkça matematik tarihini sadece bir genel kültür bileşeni olarak görmek yerine derslerinde nasıl kullanabilecekleriyle ilgilendiklerini göstermiştir. Bu nedenle, öğretmen adayları hangi matematik konusunda matematik tarihinin nasıl kullanılacağının ciddi bir bilgi birikimi ve tecrübe gerektirdiğini fark etmiş ve ders öncesinde matematik tarihi bilgileriyle ilgili sahip oldukları algıları kritik ederek değiştirmişlerdir.

Turkish Journal of Computer and Mathematics Education (TURCOMAT), 2019

Teachers use their content and pedagogical content knowledge for teaching algebra. For this reaso... more Teachers use their content and pedagogical content knowledge for teaching algebra. For this reason, the examination of how teachers use this knowledge may help shed light on how students learn algebra, especially in determining why they usually have difficulties. The aim of the current study is to reveal what teachers know, and propose what they actually need to know for teaching the simplification and equivalence of algebraic expressions. The multiple-case study design was used for this study to compare and contrast the two middle school teachers" lesson planning and instruction. The data corpus included lesson plans, actual instruction records, and post-observation interviews. Data analysis was conducted using the Mathematical Knowledge for Teaching (MKT) model. The findings indicated that both teachers had a lack of specialized content knowledge about mathematical representations such as algebra tiles. They did not use algebra tiles effectively and could not link algebraic and geometric representations that underlie the idea of multiplication. It was observed that both teachers generally used unknowns and variables interchangeably indicating the inadequacy of their common content knowledge. In the planning process, the two teachers were able to state the common misconceptions that the students generally had and the ways of addressing them. Through the cases of these two teachers, it was observed that teachers need to have a good conceptual mathematical understanding and also knowledge of students" thinking in order to design effective lessons. Based on the findings, the types of knowledge that the teachers need to have are outlined and the theoretical and practical implications of the study are discussed.

Turkish Journal of Computer and Mathematics Education, 2019

Teachers use their content and pedagogical content knowledge for teaching algebra. For this reaso... more Teachers use their content and pedagogical content knowledge for teaching algebra. For this reason, the examination of how teachers use this knowledge may help shed light on how students learn algebra, especially in determining why they usually have difficulties. The aim of the current study is to reveal what teachers know, and propose what they actually need to know for teaching the simplification and equivalence of algebraic expressions. The multiple-case study design was used for this study to compare and contrast the two middle school teachers" lesson planning and instruction. The data corpus included lesson plans, actual instruction records, and post-observation interviews. Data analysis was conducted using the Mathematical Knowledge for Teaching (MKT) model. The findings indicated that both teachers had a lack of specialized content knowledge about mathematical representations such as algebra tiles. They did not use algebra tiles effectively and could not link algebraic and geometric representations that underlie the idea of multiplication. It was observed that both teachers generally used unknowns and variables interchangeably indicating the inadequacy of their common content knowledge. In the planning process, the two teachers were able to state the common misconceptions that the students generally had and the ways of addressing them. Through the cases of these two teachers, it was observed that teachers need to have a good conceptual mathematical understanding and also knowledge of students" thinking in order to design effective lessons. Based on the findings, the types of knowledge that the teachers need to have are outlined and the theoretical and practical implications of the study are discussed.

– Algebra is generally considered as manipulating symbols, while algebraic thin king is about gen... more – Algebra is generally considered as manipulating symbols, while algebraic thin king is about generalization. Patterns can be used for generalizat ion to develop early graders' algebraic thinking. In the generalization of pattern context, the purpose of this study is to investigate middle school students' reasoning and strategies at different grades when their algebraic thin king begin s to develop. First, 6 open-ended linear growth pattern problems as numeric, pictorial, and tabular representations were asked to 154 middle g rade students. Next, two students from each grade (6 th , 7 th , and 8 th grade) were interviewed to investigate how they interpret the relationship in different represented patterns, and which strategies they use. The findings of this study showed that students tended to use algebraic symbolis m as their grade level was increased. However, the students' conceptions about 'variable' we re troublesome.

Studies reveal that students as well as teachers have difficulties in understanding and learning ... more Studies reveal that students as well as teachers have difficulties in understanding and learning of decimals. The purpose of this study is to investigate students' as well as pre-service teachers' solution strategies when solving a question that involves an estimation task for the value of a decimal number on the number line. We also examined the pre-service teachers' anticipation of students' misconceptions and difficulties for the given task. To conduct our analysis, we conducted interviews with three 5 th and three 6 th grade students, and eight preservice teachers. During the interviews we asked them to solve the question and explain their solution strategies. The findings of the study indicate that students and pre-service approach this problem in different ways. However, both groups have a tendency to think of decimals successively and indicate precise answers rather than specifying a range of possible values. We also observed the preservice teachers could only partially anticipate the misconceptions and difficulties faced by the students.

The purpose of the study is to evaluate how prospective mathematics teachers (PMTs) modify tasks ... more The purpose of the study is to evaluate how prospective mathematics teachers (PMTs) modify tasks to facilitate students' learning of pattern generalization through the use of their mathematical knowledge for teaching. Case study, which is a type of qualitative research method, was used to determine the mathematical characteristics that PMTs use when modifying a mathematical task. The knowledge from which PMTs draw to modify the task has also been outlined. Accordingly, data were collected from PMTs' task modifications and reflection reports. When PMTs worked on two or more forms of modification, as compared to just using one type of modification, they modified tasks more effectively and comprehensively. The PMTs who make condition modifications need to utilize specialized content knowledge through the use of models or tables. They aimed to help middle school students understand using these modifications, and thus they also utilized their knowledge of content and students. They also used their knowledge of content and teaching, especially while making modifications to questions and context. Task modification activities can be used to help prospective teachers notice the mathematical and pedagogical affordances and limitations offered by tasks.

Trakya eğitim dergisi, Sep 30, 2019

Ogretmen adaylarinin cebirsel dusunme ile ilgili hem kendi bilgilerini hem de ogrenciler hakkinda... more Ogretmen adaylarinin cebirsel dusunme ile ilgili hem kendi bilgilerini hem de ogrenciler hakkinda bilgilerini ortaya koymak, kavramsal bilgiye sahip olan ogretmenler yetistirmek icin ilk asama sayilabilir. Bu amacla bu calismada, ortaokul matematik ogretmeni adaylarinin oruntu genellemesi hakkindaki konu alan ve pedagojik alan bilgileri incelenmistir. Nitel arastirma tasarimi kapsaminda, 26 ogretmen adayina sabit degisen sekil oruntusu problemi ve bu problemle iliskili olarak acik uclu sorular sorulmustur. Elde edilen veriler, Ball, Thames ve Phelps (2008) tarafindan gelistirilen “Ogretmek icin Matematiksel Bilgi (OMB)” modeli kullanilarak icerik analizi ile incelenmistir. Bulgular, ogretmen adaylarinin tumunun oruntuyu cebirsel olarak dogru genelleyebildiklerini ortaya koymustur. Cogunun genellemeye ulasirken sayisal akil yurutme kullandigi tespit edilmistir. Ogretmen adaylarinin, ogrencilerin problem cozme konusundaki bilgilerinin, genellikle kendi cozum yontemlerine dayandigi gorulmustur. Ogretmen adaylarinin, ogrencilerin yasayabilecegi zorluk ve kavram yanilgilarina yonelik tahminleri oldukca sinirlidir. Dolayisiyla bunlari gidermek icin yaptiklari oneriler de yetersiz kalmistir. Bulgulara dayanarak, ogretmen adaylarini yetistirmeye yonelik oneriler yapilmistir.

İlköğretim online, Sep 15, 2020

Examining the knowledge of teachers in practice may shed light on understanding how students lear... more Examining the knowledge of teachers in practice may shed light on understanding how students learn and finding out why they have difficulty in learning. This paper focused on teachers' knowledge of pattern generalization in instruction with the consideration of students' generalization strategies in planning. The multiple-case study design was used for this study to compare and contrast two middle school mathematics teachers’ lesson planning and instruction. Lesson plans, pre-observation interviews, observations and post-observation interviews were used as the data collection tools. The data were analyzed by using the Mathematical Knowledge for Teaching (MKT) model. The findings showed that the two teachers used numerical reasoning in all representations, but they had difficulties in using figural reasoning. They generally used the tabular representation effectively to underlie the relationship of generalization. While one of the teachers defined the pattern concept correctly and always emphasized analyzing the relationship between the position number and the term, the other teacher defined the pattern concept partially correctly, and her inadequate explanations of functional thinking caused some misunderstandings of students about generalization. It was also observed that the students’ lack of knowledge about algebraic expressions prevented them from obtaining a general rule. Through the cases of these two teachers, it was noted that teachers need to have a good conceptual mathematical understanding and also knowledge of students’ thinking to design effective lessons.

Journal for the Education of the Gifted, Feb 7, 2021

Mathematically gifted students have a high potential for understanding and thinking through mathe... more Mathematically gifted students have a high potential for understanding and thinking through mathematical relations and connections between mathematical concepts. Currently, it is thought that generalizing patterns algebraically can serve to provide challenges and opportunities that match their potential. This article focuses on a mathematically gifted student’s use of generalization strategies to identify linear and nonlinear patterns in the context of a matchstick problem. Data were collected from a 10th-grade gifted student’s problem-solving process in a qualitative research design. It was observed that the gifted student’s ways of generalizing the linear and nonlinear patterns were different. In a generalization process, the student used figural reasoning in the linear pattern and numerical reasoning in the nonlinear patterns. It was noted that the student explored using Gauss’s approach in structuring the general rules of nonlinear patterns. Accordingly, aside from assisting their more gifted students, mathematics teachers may want to consider ways to introduce Gaussian thinking to the benefit of all their students.

The examination of teacher knowledge in practice can shed light to understand how students learn ... more The examination of teacher knowledge in practice can shed light to understand how students learn and find out why they have difficulty in learning. This paper will focus on teachers' knowledge of pattern generalization in instruction with planning. The multiple-case study design was used for this study to compare and contrast the two middle school teachers’ lesson planning and instruction. Lesson plans, pre-observation interviews, observations, and post-observation interviews were used as data collection tools. Data were analyzed by using the Mathematical Knowledge for Teaching (MKT) model. The findings showed that the two teachers used numerical reasoning in all representations and they could not have the knowledge of figural reasoning. The teachers' inadequate explanations of functional thinking caused some misunderstandings about generalization. Through the cases of these two teachers, it was observed that teachers need to have a good conceptual mathematical understanding...

Kastamonu Eğitim Dergisi, 2019

Bu araştırma, ilköğretim matematik öğretmen adaylarının pedagojik deneyimler içeren Matematik Tar... more Bu araştırma, ilköğretim matematik öğretmen adaylarının pedagojik deneyimler içeren Matematik Tarihi dersi öncesinde ve sonrasında matematik tarihi bilmenin gerekliliği konusunda ve kendi sahip oldukları matematik tarihi bilgileriyle ilgili algılarının neler olduğunu ve bu algılarda nasıl değişimler yaşandığını keşfetmeyi amaçlamıştır. Araştırma, ilköğretim matematik öğretmenliği programının son sınıfında öğrenim gören 32 öğretmen adayı ile gerçekleştirilmiştir. Çalışmada veriler, ders öncesi ve ders sonrası açık uçlu sorulara verilen yazılı cevaplar, öğretmen adaylarının hazırladıkları ders planları, araştırmacı notları ve derslerde yapılan sınıf tartışmaları aracılığıyla elde edilmiştir. Araştırma sonuçları, öğretmen adaylarının bir matematik öğretmenin (i) genel kültür ve saygınlık kazanmak, (ii) konu alan bilgilerini güçlendirmek, (iii) öğretim sürecini güçlendirmek ve (iv) öğrencileri matematiğe karşı duyuşsal olarak desteklemek için matematik tarihi bilmeleri gerektiği düşüncelerine sahip olduklarını göstermiştir. Pedagojik deneyimler içeren Matematik Tarihi dersi sonrasında bu düşüncelerdeki eğilimlerde ders öncesine göre belli değişimlerin olduğu görülmüştür. Diğer taraftan, araştırma sonuçları öğretmen adaylarının ders öncesinde kendi matematik tarihi bilgilerini çoğunlukla yüzeysel ve orta derece olarak tanıladıklarını göstermiştir. Ders sonrasında kendi bilgileriyle ilgili algılarında dört temel değişim ortaya çıkmıştır: (i) yüzeyselden-orta dereceye; (ii) orta dereceden-orta dereceye; (iii) orta dereceden-derine ve (iv) derinden-orta dereceye olarak gruplandırılmıştır. Elde edilen sonuçlar, öğretmen adaylarının Matematik Tarihi ile ilgili pedagojik deneyimler (ör. ders kitaplarında matematik tarihinin analizi, matematik tarihi içerikli ders planı tasarlama) yaşadıkça matematik tarihini sadece bir genel kültür bileşeni olarak görmek yerine derslerinde nasıl kullanabilecekleriyle ilgilendiklerini göstermiştir. Bu nedenle, öğretmen adayları hangi matematik konusunda matematik tarihinin nasıl kullanılacağının ciddi bir bilgi birikimi ve tecrübe gerektirdiğini fark etmiş ve ders öncesinde matematik tarihi bilgileriyle ilgili sahip oldukları algıları kritik ederek değiştirmişlerdir.

Turkish Journal of Computer and Mathematics Education (TURCOMAT), 2019

Teachers use their content and pedagogical content knowledge for teaching algebra. For this reaso... more Teachers use their content and pedagogical content knowledge for teaching algebra. For this reason, the examination of how teachers use this knowledge may help shed light on how students learn algebra, especially in determining why they usually have difficulties. The aim of the current study is to reveal what teachers know, and propose what they actually need to know for teaching the simplification and equivalence of algebraic expressions. The multiple-case study design was used for this study to compare and contrast the two middle school teachers" lesson planning and instruction. The data corpus included lesson plans, actual instruction records, and post-observation interviews. Data analysis was conducted using the Mathematical Knowledge for Teaching (MKT) model. The findings indicated that both teachers had a lack of specialized content knowledge about mathematical representations such as algebra tiles. They did not use algebra tiles effectively and could not link algebraic and geometric representations that underlie the idea of multiplication. It was observed that both teachers generally used unknowns and variables interchangeably indicating the inadequacy of their common content knowledge. In the planning process, the two teachers were able to state the common misconceptions that the students generally had and the ways of addressing them. Through the cases of these two teachers, it was observed that teachers need to have a good conceptual mathematical understanding and also knowledge of students" thinking in order to design effective lessons. Based on the findings, the types of knowledge that the teachers need to have are outlined and the theoretical and practical implications of the study are discussed.

Turkish Journal of Computer and Mathematics Education, 2019

Teachers use their content and pedagogical content knowledge for teaching algebra. For this reaso... more Teachers use their content and pedagogical content knowledge for teaching algebra. For this reason, the examination of how teachers use this knowledge may help shed light on how students learn algebra, especially in determining why they usually have difficulties. The aim of the current study is to reveal what teachers know, and propose what they actually need to know for teaching the simplification and equivalence of algebraic expressions. The multiple-case study design was used for this study to compare and contrast the two middle school teachers" lesson planning and instruction. The data corpus included lesson plans, actual instruction records, and post-observation interviews. Data analysis was conducted using the Mathematical Knowledge for Teaching (MKT) model. The findings indicated that both teachers had a lack of specialized content knowledge about mathematical representations such as algebra tiles. They did not use algebra tiles effectively and could not link algebraic and geometric representations that underlie the idea of multiplication. It was observed that both teachers generally used unknowns and variables interchangeably indicating the inadequacy of their common content knowledge. In the planning process, the two teachers were able to state the common misconceptions that the students generally had and the ways of addressing them. Through the cases of these two teachers, it was observed that teachers need to have a good conceptual mathematical understanding and also knowledge of students" thinking in order to design effective lessons. Based on the findings, the types of knowledge that the teachers need to have are outlined and the theoretical and practical implications of the study are discussed.

– Algebra is generally considered as manipulating symbols, while algebraic thin king is about gen... more – Algebra is generally considered as manipulating symbols, while algebraic thin king is about generalization. Patterns can be used for generalizat ion to develop early graders' algebraic thinking. In the generalization of pattern context, the purpose of this study is to investigate middle school students' reasoning and strategies at different grades when their algebraic thin king begin s to develop. First, 6 open-ended linear growth pattern problems as numeric, pictorial, and tabular representations were asked to 154 middle g rade students. Next, two students from each grade (6 th , 7 th , and 8 th grade) were interviewed to investigate how they interpret the relationship in different represented patterns, and which strategies they use. The findings of this study showed that students tended to use algebraic symbolis m as their grade level was increased. However, the students' conceptions about 'variable' we re troublesome.

Studies reveal that students as well as teachers have difficulties in understanding and learning ... more Studies reveal that students as well as teachers have difficulties in understanding and learning of decimals. The purpose of this study is to investigate students' as well as pre-service teachers' solution strategies when solving a question that involves an estimation task for the value of a decimal number on the number line. We also examined the pre-service teachers' anticipation of students' misconceptions and difficulties for the given task. To conduct our analysis, we conducted interviews with three 5 th and three 6 th grade students, and eight preservice teachers. During the interviews we asked them to solve the question and explain their solution strategies. The findings of the study indicate that students and pre-service approach this problem in different ways. However, both groups have a tendency to think of decimals successively and indicate precise answers rather than specifying a range of possible values. We also observed the preservice teachers could only partially anticipate the misconceptions and difficulties faced by the students.