Not a student or an instructor, but hope you don't mind me replying.
I wasn't taught to say that I was a student, although I was made aware the option was available if I chose to use it. I think it's better not to. After all, some time fairly soon, these students aren't going to be students any more. Nothing magically changes when you pass your skills test - you don't suddently become confident at R/T or suddenly become able to hold your height to 20' and your heading to 2 degree when asked - those things come gradually over time. So I think it's important for students to be treated exactly the same way by ATC when they are students as they will when they are no longer students.
(How many of us were just a little shocked when we first ripped the L-plates off our cars, only to find that suddently every other driver starts hooting at us because we're going a little slower than them, or being a little more cautious at junctions? I think the green P-plates that new drivers have now are great, since they avoid that - but there's no standard R/T to say that you're a "recently qualified pilot".)
FFF
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