Penelitian yang digunakan pada penelitian ini yaitu penelitian Tindakan Kelas (PTK). Penelitian Tindakan Kelas digunakan dengan tujuan untuk meningkatkan kemampuan menulis teks deskripsi menggunakan model pembelajaran think talk write dengan media lingkungan alam. Media lingkungan alam yang digunakan sebagai objek pengamatan ialah berupa Asrama, sekolah, kantin, Kolam dan Musholla. Penelitian ini dilaksanakan dalam II siklus yang setiap siklus terdiri dari 4 tahap diantaranya perencanaan, pelaksanaan tindakan, observasi atau pengamatan, dan refleksi. Hasil ketuntasan siswa ranah kognitif siklus I sebesar 50% mengalami peningkatan pada siklus II menjadi 84,37%, Ranah afektif pada siklus I sebesar 68,75% mengalami peningkatan pada siklus II sebesar 93,75%, Pengamatan aktivitas siswa pada siklus I sebesar 60,63 mengalami peningkatan pada siklus II sebesar 90,71, Pengamatan aktivitas guru pada siklus I sebesar 68,35 meningkat pada siklus II sebesar 91,40. Berdasarkan Hasil tersebut menunjukkan bahwa pembelajaran menulis teks deskripsi menggunakan model pembelajaran think talk write (ttw) dengan media lingkungan alm dapat meningkatkan kemampuan menulis teks deskripsi pada siswa kelas VII di MTs Al-Fatah Tarakan, Hal tersebut dikarenakan hasil penilaian pada aspek kongnitif dan afektif telah mencapai indikator persentase keberhasilan yaitu 75%.

The research used in this research is Classroom Action Research (CAR). Classroom Action Research is used with the aim of improving the ability to write descriptive text using a think talk write learning model with natural environment media. Natural environmental media used as objects of observation are in the form of dormitories, schools, canteens, pools and prayer rooms. This research was carried out in two cycles, each cycle consisting of 4 stages including planning, implementing actions, observing or observing, and reflecting. The results of student mastery in the cognitive domain in the first cycle of 50% increased in the second cycle to 84.37%, the affective domain in the first cycle of 68.75% experienced an increase in the second cycle of 93.75%, the observation of student activities in the first cycle was 60 ,63 experienced an increase in the second cycle of 90.71, the observation of teacher activity in the first cycle of 68.35 increased in the second cycle of 91.40. Based on these results indicate that learning to write descriptive text using the think talk write (ttw) learning model with late environmental media can improve the ability to write descriptive text in class VII students at MTs Al-Fatah Tarakan, this is because the results of the assessment on cognitive and affective aspects have been achieve the percentage of success indicator that is 75%.