Which clipless pedal is right for me?

I am a 12 year old road bike fanatic. Right now I am going on hilly 45 mile rides, and would love to go even farther. Recently I became interested in getting clipless pedals, upgrading from the clips I use now. These are my criteria: $50-80, easy to clip in/out (I bike to school through traffic), and relatively easy to use. Since these would be my first pair, I would definitely want ones that are not pro grade. Weight does not matter. Thanks!

I have looked up the Shimano SPD, and it looked nice. However, there were two models on the site, the A520 and the A530. Which one should I get?

There are several different kinds of clipless pedals for you to choose from and it depends on the riding you do.
If you commute at all, then I suggest the Shimano spd pedals that are half clipless, half platform. Those are good for a few reasons, 1, if you don't like clipping in, or don't get the hang of it right away, it gives you a chance to ride without them, 2, if you ever just jump on the bike to ride a few blocks for an errand or something, you can wear regular shoes. However, those pedals are generally mtn. shoes. Shimano also makes a road pedal (shimano spd-sl ) that have a large base for you to clip into which would work if you just hopped into the bike to commute as well because it's large enough to support regular shoes.
Another thing to consider, the kind of shoes you want. I have several cycling shoes and clips to go with them. If you want cycling shoes, then it doesn't matter what kind of pedals you get, but if you want shoes that you can walk around in for errands, then you would want more of a mtn cleat because they would be recessed so you can walk around in them.
Egg beaters (or anything made by crank brothers) are generally very easy to clip in and out of, but there isn't much of a base to them if you aren't clipped in.
The third thing to consider is how you want to clip in. If you want to clip in by pressing your foot straight down, then you'll want something like the speedplays, shimano spds, or egg beaters. But if you like the idea of pushing forward, then look pedals or shimano spd-sl would work too.
I don't know how much each of these cost, but there are some things for you to think about.

The three I use are Shimano SPD-SL for my road bike, Crank brothers Smartys for my mtn bike, and shimano spd/platform combo for my commuter.

PD-6620-G or PD-R540(this model has the pro team series if their still in stock, has teams like discovery and t mobile)

I own the discovery version of the 540 and have tried the 6620
all comes with the variable tensioner so you can increase it as your skill improves

in that price range, go with Shimano SPD's. they're double sided, so they're easier to learn on than some of the more expensive pedals..