Life guarding is by far the easiest job and best job ever. If the pay was really good I would do it for the rest of my life.
The class is easy as shit and unless you are a complete dumb ass you will pass it with ease.
A five hundred is pretty far if you are racing but they will just make you swim it and it is super easy juat take your time.
The hardest shit to remember is CPR but I highly suggest you get a lifeguard job, hot girls are lifeguards, you get to yell at little kids, and you get to have fun in the sun.