Copying feature classes using Export
You can copy a series of geodatabase feature classes from one geodatabase to another using the Export tool. Right-click the name of the geodatabase that contains the feature classes you want to copy, point to Export, then click To Geodatabase (Multiple)
The Feature Class to Geodatabase (multiple) geoprocessing tool dialog box opens.
This dialog box is populated with a list of feature classes. You can remove feature classes from the list or add new ones by dragging and dropping them into the window or browsing to their location. By default, all the feature classes in the existing geodatabase will be automatically copied unless you modify the list of feature classes.
You'll need to type the name of an existing geodatabase into which the feature classes will be copied.
Be aware that only simple feature classes will be copied. For example, if you have feature classes contained within feature datasets to be exported, only the feature classes will be copied. The feature dataset, plus any of its advanced elements, such as topologies, geometric networks, and terrains, will not be copied to the output geodatabase.