Im looking into getting beter at soldering and am wondering what are some good beginner pedals to make?
A line selector or A/B would be easiest. From there you can go to something like an MXR Distortion+ or a booster. Dist+ would be more advisable because the booster has transistors which are super heat sensitive and if you're learning to solder you could fry it.

If you're just looking to learn you should really just get some broken PCB and solder and desolder wires into it for practice.
my first project was tweak-o. a complete kit is available from smallbearelec.com. it's an ok sounding fuzz. it's easy with step by step instructions. the fuzz intensity knob doesn't do much.

if you're not completely clueless and can make a shopping list of parts, i recommend the muff boost http://www.muzique.com/schem/projects.htm. it's got a great thick fuzz sound for solo sounds. sounds better than the tweak-o and just as easy to make.

the minibooster http://www.muzique.com/amz/mini.htm is a nice cleanish boost with an overdrive sound. increase R5 to 4.7k-10k for less distortion.

all of these are low part count and have easy to get parts.