I have two questions.
In the UK, to do (or is it read?) a roll call is commonly referred to as "calling
out the register". It's been so long since I was a child that I'm not absolutely sure how students responded. I think it was "Present, miss/sir"
I also seem to remember students just raising their hands. Are there different responses in the rest of the English speaking world?
Secondly, I am experiencing difficulty in pronouncing roll call. I can say each word separately without any trouble but when I join the two together it sounds as if I'm saying "rolkol"; "rolekol" or "rol kol" I've looked in wiktionary and TFD but neither have the pronunciation. Should I pronounce roll in "roll call" as /rəʊl/ or /roʊl/?
It seems responding to the roll call with "present" has become dated both in the UK and the US whether it holds true for Canada and Australia is unknown. Apparently, British students responded with "Yes, miss/sir" until the 70s but now the simple, "Here" is heard on both sides of the Atlantic. The Longman Contemporary English Dictionary, claims that call/take the register is old fashioned in the UK, but I wonder if that really is the case, and whether in the US "calling the roll" is becoming dated as suggested by the Google Ngram chart in @bib's answer.