A B S T R A C TThe relationship between temperature and humidity of air and visibility of mirage has been studied by observing mirage on the runway of Sultan Iskandar Muda International Airport (SIM) Aceh, Indonesia. Temperature and humidity data were obtained from BlangBintang Meteorology, Climatology and Geophysics Station's database, Aceh Besar, Aceh, Indonesia. It was observed that mirage has shown up from morning to afternoon, from 07.00 AMuntil 18.00 PM, even until sunset. Mirage is also still visible when the weather is cloudy or drizzling, but disappeared when heavy rain. The lowest and highest temperatures where the mirage can still be observed are 26.0 0 C and 32.0 0 C, respectively. Meanwhile, the lowest and highest air humidities where mirages can still be observed are 51.0% and 92.0%, respectively. Observation shows that changes in temperature and humidity in the runway environment greatly affect the appearance and visibility of mirages. When the air temperature is high and the humidity is low, the mirage appears with high visibility (very thick), so that it can be observed clearly visually. Conversely, when the temperature of air is low and the humidity is high, mirage appears with low visibility (very thin) or almost non-existent or completely gone.

Pembelajaran dikelas dapat berjalan dengan baik jika proses pembelajaran juga berjalan dengan baik. Penelitian ini bertujuan untuk mengetahui aktivitas siswa terhadap penerapan media Word Square dalam pembelajaran kimia pada materi struktur atom, mengetahui hasil belajar siswa dengan menggunakan media Word Square pada materi struktur atom dan mengetahui respon siswa terhadap penerapan media Word Square dalam pembelajaran kimia pada materi struktur atom. Teknik pengumpulan data yang digunakan pada penelitian ini adalah lembar observasi, tes berupa pre-test dan post-test dan angket respon. Hasil penelitian menunjukkan bahwa 1) Aktivitas belajar siswa terhadap penggunaan media pembelajaran word square pada materi struktur atom sangat baik, berturut-turut sebesar 79,17 dan 83,00. (2) Hasil belajar siswa terhadap penggunaan media pembelajaran word square pada materi struktur atom yaitu sebesar 92,59. (3) Respon siswa terhadap penggunaan media pembelajaran word square pada materi struktur atom sangat positif, yaitu sebesar 91,66 dan respon negatif yaitu sebesar 8,33.

Community service activities have been carried out at SD Negeri 9 Dewantara. This service program aims to introduce basic measuring tools to improve and support student science learning which starts from grade IV of Elementary School. The basic measuring tool introduced is the measuring tool for length. The material presented includes names, functions and how to use ruler measuring instruments, calipers, and screw micrometers. The introduction of measuring instruments with the inquiry method or direct practice is proven to improve students' science process skills. This is because students are actively involved in every learning process.

This Community Service activity aims to explain the use and benefits of the Mendeley application to prospective teachers. This activity was carried out for two days from 5-6 June 2023. The stages of this activity consisted of the preparation stage, the implementation stage and the evaluation stage. The community service activities that have been carried out have succeeded in increasing the knowledge and understanding of participants in using and utilizing the Mendeley application for writing scientific papers.