Yes this is a credible website. I know I've seen people on here before who said they were teachers, but I don't know from which schools. Typically, I think they've been highschool teachers more so than college professors. You might want to talk to someone who lives in Europe, as I don't even have a clue how European schools work. And you should have asked this in the off-topic board as this is what someone might consider hijacking the thread.
I have more plants to do still, it's been raining and then I had my alumni dinner last night. Might get one or two more leaves done tonight.