Welcome to the forum.
I don't see anything in your post that hints at an intern not being ALLOWED to see a particular record, so I wont get into reccord access privileges. Lets start with convenience...thats what I see you asking for.
Each record should be tagged with the person who is responsible for updating it. Each intern, then, can search for their name in that field and be left with a 'found set' of their own records.
Create a field called "intern" and place it on the layout.
If desired, look under Format>Sliding and Printing and check off not to print this field.
Now create a custom value list under File>Manage>Value Lists and type in your 5 account names.
I will assume that each intern has their own account...if not, make it so...it will help.
The value list may look like:
tjones etc. with a retun after each in the list.
Now change the field setup on your layout to be a drop-down list using that value list.
As you go through the records, which it appears you need to do anyway, simply select via the dropdown menu who should be working on it.
Now put a button somewhere on the layout saying "Find Mine".
That button should perform a find for Table::Intern = Get(AccountName).
Now a single click of that button will put each intern into a found set of the records that they need to update.
I would go a step further and put a "Done" field on the layout that can be marked when the record is updated. If you do this, the find step above would find not only when the "Intern" field matches the Account name, but also when the Done field is empty.
If you want this feature, have your "find mine" button perform the following script:
Enter Find Mode
Setfield [ Intern ; Get(AccountName) ]
SetField [ Done ; "=" ]
Perform Find 
The "=" will search for records in which that field is empty.
I am assuming the vocabulary I used is acceptable. If you need more detail, please feel free to ask.
I'm sure that Ninja's reply is the best approach but I'm lazy so I'll suggest an easier way.
…Their batch is mostly sorted and distributed by year…
You probably have the "year" defined as a field in your table. If it is not on your layout, add it.
Show your interns how to enter find mode and enter a value for the year. This will limit their "found set" to records for that year until they perform another find.
Nice one Jade...much easier if it meets the need.
I saw my post becoming a novel already...and I was on dial-up over the weekend. Thanks for the add-on.
Thank you Ninja and Jade, I think we'll test both methods and see what's more efficient for our situation. I'm wondering if there is a way to change a field for multiple records at the same time.
Check out Replace Field Contents in the record menu.
It's a good idea to save a copy of your file first when you first test this one out as it can change large numbers of records in one step.