He goes to Meiryo?? Like the school Kurata wanted to go to??? The school for smart kids???
On another note, Tetsuki should at least inform the club advisors to give them a heads-up in case anything happens.
Personally, I prefer keeping -kun/-san/-sama prefixes because they give insight into the realationship dynamics between the characters. I do agree about translating the -sensei suffix though, since "sensei" can be used to address people from different professions.