This worksheet guides the student through the process of adding and subtracting numbers expressed in scientific notation. This is part 2 of the scientific notation series (Lesson 1). This worksheet opens by teaching the student how to manipulate numbers in scientific notation without changing their value. Then the student applies the rule of manipulation in order to add and subtract numbers expressed in scientific notation. A key is included and the worksheet is in landscape format for ease of use with a document cam. Enjoy!