📁 课程计划
Sites that contain lesson plans for science. Lesson plans usually contain such information as: age level, required materials, objective, clear instructions or procedure.
条目 (7+)
Some Early Microscopes from the Optical Institute in Wetzlar
http://www.antique-microscopes.com/kellner/kellner1.html
Superliminal Software - The Geometry Page
http://www.superliminal.com/geometry/geometry.htm