Grading systems do vary heavily. In my school they can vary from teacher to teacher. For example, most of the physics teachers grade out of 4: getting a 4 means you went 'above and beyond' and you need a certain number of those to get an A. My Lit teacher grades with a ton of decimals: 17.6 out of 20 points, etc. He also grades projects on different criteria every time, which takes some getting used to.
Alright, so here in Texas we have our own edjumukahin sistim ande ief ah weer two jujje haw wayhul eit eis werkhing, ah wod givv it ay 11/10 (wich is abviisly thee numbar Texas).