Tujuan Penelitian ini adalah untuk meningkatkatkan hasil belajar negosiasi pada siswa kelas X Pemasaran 3 di SMK Negeri 1 Sukoharjo melalui penerapan model pembelajaran  kooperatif think pair share dengan pendekatan saintifik (scientific approach).
Penelitian ini merupakan Penelitian Tindakan Kelas (PTK ) . Penelitian dilakukan dalam dua siklus, dengan tiap siklus terdiri atas perencanaan, pelaksanaan tindakan, observasi dan refleksi. Subjek penelitian adalah siswa kelas X Pemasaran 3 SMK Negeri 1 Sukoharjo yang berjumlah 36 siswa. Sumber data berasal dari siswa, guru, data dan dokumen. Teknik pengumpulan data adalah dengan observasi, tes, dokumentasi dan wawancara. Teknik untuk keabsahan data menggunakan triangulasi sumber data. Analisis data menggunakan teknik analisis deskriptif dan teknik analisis secara kualitatif.
Hasil penelitian menunjukan bahwa melalui penerapan model pembelajaran kooperatif think pair share dengan pendekatan saintifik ( scientific approach ) dapat meningkatkan hasil belajar negosiasi. Peningkatan terjadi pada siklus I, walaupun belum optimal. Pelaksanaan siklus II menyebabkan hasil belajar siswa mencapai kualifikasi sangat tinggi.
Simpulan penelitian ini adalah penerapan model pembelajaran kooperatif think pair share dengan pendekatan saintifik (scientific approach) dapat meningkatkan hasil belajar negosiasi pada siswa kelas X Pemasaran 3 SMK Negeri 1 Sukoharjo.

Kata kunci: think pair share, Pendekatan Saintifik, hasil belajar

The objective of this research is to improve learning achievement of the students in Grade X  Marketing Class 3 of State Vocational High School 1 Sukoharjo through the application of cooperative learning model think pair share with the scientific approach.
This research is a Classroom Action Research (CAR) . The study was conducted in two cycles, with each cycle consisting of planning, action, observation and reflection. The subjects were students in Grade X  Marketing Class 3 of State Vocational High School 1 Sukoharjo totaling 36 students. Source of data derived from students, teachers, data and documents. Data collection techniques are observation, testing, documentation and interviews. Techniques for the validity of the data using triangulation of data sources. The data analysis using descriptive analysis techniques and qualitative analysis techniques.
The results shows that through the application of cooperative learning model think pair share with a scientific approach (scientific approach)  can improve the students’s learning achievement in Negotiations subject matter. The improvement occurred in the first cycle, although not optimal. Application of the second cycle causes the learning acheivement of students achieving very high qualification.
The conclusions of this research is the application of cooperative learning model types think pair share with a scientific approach can improve learning achievement of  Negotiations subject matter  in Grade X Marketing Class 3 of State Vocational High School 1 Sukoharjo.

Keywords: think pair share, Scientific Approach, learning achievement