[debjit]

Really the only way to handle that is using AJAX handlers so JS/PHP to store the student's answers to cookies. Once the exam is completed and submitted you can clear the cookies used. I would also say I plan for the future in your initial development. If you are going to add higher level management to the system possibly down the road, then add the framework for that into the code now. That way you are not having to retool entire systems, modifying and upgrading the database and so on to add in an "School Administration" tier. These could be systems and protocols you add in now (ranks, rank access permissions etc.) that sit there until a time comes that you are ready for it. I just know with my devs, I made rookie mistakes not looking forward and having an "oh s***" moment when I had to recode entire features.

I am using Laravel and Livewire for this purpose. I have created already a subject with livewire and laravel. The livewire part is very simple and it takes care of js and ajax without any js code. I will be sharing my journey creating this application on Twitter Facebook and LinkedIn. So follow me there and I am thinking it will be completed within a month.

I am creating this app as a give to all my teachers, so they can easily make use of it and reach more students for absolutely free. 
I may create a school management system but I am not very sure about this idea.