<![CDATA[Mode is one of the measures of central tendency that students often learn procedurally by identifying the most frequently occurring value, without understanding its meaning in real-world situations. This study aimed to design a learning trajectory for mode using a PMRI-STEM approach and a coffee grinder context to support students’ conceptual understanding and contextual reasoning in vocational mathematics. The study employed a design research approach consisting of preliminary design, teaching experiment, and retrospective analysis. The participants were 25 Grade 10 students in a Culinary Arts Vocational High School. Data were collected through classroom observations, student worksheets, interviews, and learning documentation and were analyzed descriptively to examine students’ learning processes and strategies. The resulting learning trajectory involved activities in adjusting coffee grinder settings, grinding coffee beans at different grind sizes, observing brewing characteristics, organizing preference data into frequency tables, and identifying the mode as the most frequently selected grind size. The findings showed that students were able to determine the mode and interpret it as an indicator of majority customer preference for determining standard coffee shop menu settings. Students also connected grinder settings, brewing results, data representation, and statistical decision-making through contextual reasoning. These findings suggest that a PMRI-STEM approach using a coffee grinder context can support students’ understanding of mode and develop contextual statistical literacy in vocational mathematics learning.]]>
