The article describes a few cases in which mathematics teachers used graphing calculator to instruct secondary mathematics. It demonstrates graphing calculators are powerful tools when used appropriately .and they should be integrated in mathematical curriculum for all grades where problem solving and mathematical modeling is the main focus. The article describes the idea for developing mobil E ぴC Lab in Secondary School where flexible combination of graphing calculators and other technology to meet different needs of implemention of "New Mathematics Curriculum".