<![CDATA[This development research aimed to know effectiveness and response of learners using guided inquiry method based worksheet in term of mathematical communication ability and student’s self-efficacy. This study was initiated with preliminary studies (need analysis), the composing, the validation, preliminary field testing, and the field trial of worksheet. This development research follows the paths of Borg and Gall. The subject of this research was student of X Perbankan 1 class of SMK Yadika Pagelaran. Data collected through observation, interwiew, questionnaires, and tests. The data analyzed using quantitative and qualitative descriptive analysis techniques. The field trial results showed that (1) worksheet is effectively used because more than 70% of the students score obtain a value greater than or equal to reached minimum criteria on a mathematical communication skill test, (2) the student’s self-efficacy after used worksheet did not show any significant changes, (3) the student’s response to the worksheet has met good criteria of aspects of appearance, presentation of materials, and benefits.Penelitian pengembangan ini bertujuan untuk mengetahui efektivitas dan respon peserta didik yang menggunakan LKPD berbasis metode guided inquiry ditinjau dari kemampuan komunikasi matematis dan self-efficacy siswa. Penelitian pengembangan ini mengikuti alur Borg and Gall. Subjek penelitian pada uji lapangan adalah siswa kelas X Perbankan 1 SMK Yadika Pagelaran. Data dikumpulkan melalui observasi, wawancara, angket dan tes. Data dianalis menggunakan teknik analisis deskriptif kuantitatif dan kualitatif. Hasil uji lapangan menunjukkan bahwa (1) LKPD efektif digunakan karena lebih dari 70% siswa memperoleh nilai lebih dari atau sama dengan kriteria ketuntasan minimal pada tes kemampuan komunikasi matematis, (2) self-efficacy siswa setelah menggunakan LKPD tidak mengalami perubahan yang signifikan, (3) respon peserta didik terhadap LKPD telah memenuhi kriteria baik dari aspek tampilan, penyajian materi, dan manfaat.Kata kunci: LKPD berbasis metode guided inquiry, komunikasi matematis, self-efficacy]]>
