available

What sentences?

-On the form we're providing herewith please tick boxes indicating appropriate times for you to be available for class, tutorial, lecture, etc

Thank you. But the sentences would be said in class, not printed on paper; why HEREWITH?

So you would say something much simpler.

Something like:
"I am giving out this sheet.
When you get your copy, put your name on it, and tick the box to show when you are available for tutorial.
I'll collect them at the end of the class."

What sentences

I had supposed your message was distributed in, say, printed form

Thus your OP, WB, needs clarification

Thank you~