That is 'This Is Not a Test' by twentysomething.

"Max Winchester is living probably the most boring life on the planet. He's 12 years old, which is boring, he has two older siblings, which- Abby and Jack are cool- but that's boring, too. His parents run a body shop, and yeah, it's sort of cool that all these rich people come begging to Dad to fix their cars, but it's not like Tom's dad, who's a firefighter or Jimmy's dad, who is a surgeon. Uncle Sam is lawyer and Bobby is, well Bobby. They never go anywhere, they never do anything and Max thinks that banana slugs have a more interesting life than he does."

http://archiveofourown.org/works/154606

Thanks so much!!!!