In this activity, learners will measure the length of their shadow from the Sun and compare it three to four months later. This process will help learners investigate Earth's rotation and discover the change in seasons by the elevation of the Sun. This resource includes an explanation of why learners will observe changes in their shadow's length as well as a description of Eratosthenes' first known measurement of the circumference of the earth. Learners can measure the circumference of the Earth using shadows in the related activity "The Shadow Knows II." This resource also includes winter and summer safety tips.


  • Mathematics > General
  • Education > General

Education Levels:

  • Grade 1
  • Grade 2
  • Grade 3
  • Grade 4
  • Grade 5
  • Grade 6
  • Grade 7
  • Grade 8
  • Grade 9
  • Grade 10
  • Grade 11
  • Grade 12


Data Analysis,equinox,NSDL,Sun,orbit,NSDL_SetSpec_ncs-NSDL-COLLECTION-000-003-112-056,Reflection and Refraction,Space Science,Mathematics,Earth, Moon and Sun,analemma,The Sun,Early Elementary,Data Collection,Upper Elementary,Eratosthenes,solstice,Atmospheric science,Solid Geometry,Rotation Motion,Seasons,Size and Scale,Informal Education,Circles,Middle School,Formulating Explanations,Gathering Data,The Moon,Days,Weather and Climate,Elementary School,General science,Conducting Investigations,oai:nsdl.org:2200/20110926132702693T,rotation,Chemistry,Physics,shadows,circumference,Earth system science,General,Sunlight and Color,Space science,Measurement,Physical science,Education,Geoscience,Light and Optics



Access Privileges:

Public - Available to anyone

License Deed:

Creative Commons Attribution Non-Commercial Share Alike


This resource has not yet been aligned.
Curriki Rating
'NR' - This resource has not been rated
'NR' - This resource has not been rated

This resource has not yet been reviewed.

Not Rated Yet.

Non-profit Tax ID # 203478467