DOI: 10.5064/f6mao6tq
title: Data for: Why Is Secondary School Mathematics Difficult to Learn? From the Perspectives of In-Service Teachers and Cognitive Load Theory

description: &lt;h3&gt;Project Overview&lt;/h3&gt;
&lt;p&gt;This research explores the complexity of secondary school mathematics through the perspectives of experienced in-service teachers and the framework of cognitive load theory. The research identifies sources of complexity in learning mathematics and compares them with the definitions of complexity within cognitive load theory. Semi-structured interviews with eleven secondary school mathematics teachers were conducted reaching empirical-driven saturation. The analysis of these interviews highlighted complexity sources related to the inherent intricacy of mathematics (knowledge complexity) and to the form in which tasks and instruction is presented and designed (task complexity). The findings offer insights into the nature of the difficulties students encounter while learning mathematics and thus provide an approximation to the sources of complexity that should be considered when assessing secondary school mathematics. The conclusions provide a bridge between academics and daily teaching, enhancing the applicability of cognitive load theory.&lt;/p&gt;
description: &lt;h3&gt;Data and Data Collection Overview&lt;/h3&gt;
&lt;b&gt;Participants and Recruitment&lt;/b&gt;
&lt;p&gt;Participants (N = 11) were experienced secondary school mathematics teachers from three different schools in Catalonia. All participants had at least five years of teaching experience in mathematics and taught across grades 7 to 12. Recruitment followed a convenience-sequential sampling strategy: initial participants were identified through professional teaching networks and institutional contacts within secondary schools in the Barcelona metropolitan area, and subsequent participants were added iteratively until data saturation was achieved. Teachers were selected based on accessibility and willingness to participate, and the sample was monitored continuously to determine when no new conceptual insights emerged in interview analysis. All participants provided written informed consent and retained the right to withdraw at any time without justification.&lt;/p&gt;
&lt;b&gt;Data Collection Procedure&lt;/b&gt;
&lt;p&gt;Interviews were face-to-face, conducted in Catalan or Spanish according to participants’ preference, and audio-recorded with consent. Each session lasted between 20 and 50 minutes. The interview protocol was semi-structured and designed to explore:
&lt;ol&gt;
 &lt;li&gt;The perceived sources of complexity that students experience in mathematics learning.&lt;/li&gt;
 &lt;li&gt;Teachers’ comparisons of different mathematical topics and problems in terms of difficulty and cognitive demand.&lt;/li&gt;
 &lt;li&gt;The factors contributing to task and knowledge complexity in classroom instruction..&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt; To guide discussion, teachers analysed a learning sequence on fraction operations drawn from a Catalan Year-7 mathematics textbook aligned with the national curriculum. The interview included both conceptual questions about mathematics content (e.g., “Which topics do students find most complex?”) and applied tasks (e.g., “What aspects of this problem increase its complexity for students?”).&lt;/p&gt;
&lt;p&gt;All interviews were transcribed verbatim following O’Connell and Kowal’s (1999) standards for qualitative transcription. &lt;/p&gt;
description: &lt;h3&gt;Selection and Organization of Shared Data&lt;/h3&gt;
&lt;p&gt;The data files shared here consist of 11 interview transcripts. The documentation files shared comprise the interview guide, the consent form used in the study, this Data Narrative, and an administrative README file.&lt;/p&gt;