If you right click in the player window and choose the 'Debug' option, the following window will appear:-
This shows the different scripts that are running, and displays the current values of top level variables.
You can also get/set variables and execute functions using the 'Execute Script Now' text box.
Examples
Type print("hello"); into the box and click Execute. This will cause the console to display 'hello'.
Type scenes.scene_1.script.myvar=2; into the box and click Execute. This will set the current value of 'myval' in 'scene_1' to 2.
Type scenes.scene_1.script.myvar into the box and click Execute. This will show the current value of 'myval' in 'scene_1' in the 'Result' box.