I am sending identical tasks/questions (pdf by email) to a group of students who are at very different levels.
In order to make it interesting for all of them, I would like to supplement the tasks with hints, e.g. (1) no hints for the good students, (2) a small hint for intermediate students and (3) a larger hint for weaker students.
I would like to leave those hints online (with a link in the pdf) so that students can download them as needed. It is not a test situation and I trust the students, so there is no need to track who used what hint (though that could be nice feature if possible).
Is there an easy way to set this up with tools that are readily available (I don't want to build my own web server or have the students install anything.)? The hints would only be short snippets, nothing big.