Four observational astronomical item, have been pilottested with a 150mm refracting telescope in order to layout the detailed procedures for the suggested (inquiry) activities listed in the high school earth science curriculum and to contrive some adequate instructions for students stressed on how to make proper treatments with the collected materials. The tested items were of sunspots' motion, the size of lunar craters, the Galilian satellites' revolution, and the galactic distribution of stars. Following series of activities are suggested with respect to the way of collecting observational data and of giving proper instruction to students in class: 1) Photography and other material, he made by teacher and/or extracurricular group of students; 2) Replicas (xeroxed, photographs, Or slides) he made from the collected materials, '0 that they are available to all the students in class; 3) Quantative analyses, be taken as student' activity.