For an assignment or report of an investigation, you will want to keep datasets, tables and pictures for later use, print or paste into a document. Here are some tips.
Save a dataset
You need a Google Drive account, make sure it's active.
In the Data Analysis app, open the menu 
and select Save in Google Drive
You must enter a name, a confirmation will be displayed later.
You can save a dataset in Excel. Select the dataset or part of it.
Copy it and paste it into an Excel worksheet. However, you only have the bare data.
Save a crosstab
In the apps Crosstab Analysis and Resampling Crosstabs
You need a Google Drive account, make sure it's active.
In the Crosstab app, open the menu and select Save in Google Drive.
You must enter a name, a confirmation will be displayed later.
Save and print a chart or table as an image
It is useful to use a screen capture program.
In Windows, you get the Easy Capture Manager with the PrtScr button.
You can then select, save and edit a desired part of the screen.