Hi, is there a way to check if a slide have been viewed?
what i want to do is to add score to an objetive when a user enter a specific slide. There is a function for this but if the user reloads the slide or enter more than once , the score will be added. I would to add the score only once. Unfortunatelly setting the score to a specific value is not usefull because this objective can have different values when the user enters this slide.

Use a variable that is set to 1 if the slide has been visted. Then use an If statement to display text if it hasn't

AS Bob says you can define a variable to hold this, it will need to be a global variable and a good idea is to give it a proper name like Page1Read.
It's initial value should be 0.
So when the user opens the page you have an action onload or onready to see if it has been read which would be something like. Note this isn't the real code just the steps
If page1read=0
.set page1read=1
(changes the value once opened if NOT already opened)
..set score to +1
(then updates the score)
You might also want to think about using objectives, here you could say a module or an onjective isn't completed until pages n,n,n or n to n have been opened.