Geoscience teaching using local geological materials (2): Observation of sedimentary layers with the activities of expectation and debateHirofumi Yamasaki, Tomonori Nishimura, Takehiro Hayashi, and Morihisa Suzuki We planned and tried a learning program of observation of sedimentary layers for undergraduate and high school students. The purpose of the program are to get basic skill of observation of strata and to understand the arrangement of layers in space on the basis of recognition of feature of strata, expectation and debate on the correlation of layers, and verification of the result of debate. The flow of the activities in the program is the following order, (1) to observe the layers at outdoor cliff or the peeled sample of strata in a classroom, (2) to make columnar section in the field observation and to sketch the peeled sample of sedimentary layers, (3) to estimate the correlation of layers, (4) to debate on the estimation, and (5) to verify the result of debate. The process of the program made the students watch the layers carefully in this trial case.