instead of useing %quizq != $null or %quizq == $null you could do !%quizq an %quizq
also on ur unset of vars you can do unset %quizy %quizn %quizq %voter or beter yet why not name the vars like %vote.quizy %vote.quizn %vote.quizq and %vote.vote then unset them like unset %vote.*

you do have alot of redundancy in the script but good work on ur first script.