Does size matter? lol

Yes it does, we are told all the time that 10cm rulers are useless to us because we usually work with with A4 paper and the ruler simply Isn't long enough, but you can't go all out and get a 40cm one because then it won't fit in your pencil case. So I recommend a 30cm metal ruler, that way it fits in your pencil case and it wont snap

If you have a question, here is the place to ask it. Except if it's about those cheezles, it was empty when I got there.