What are some really good drills for getting a better guard? I find myself there alot and have problems keeping someone there. They pass to easy because I can't use my open guard well.

there is a excersize that helps strengthen your guard and keep your knees in- it is mostly a stomach excersize though

You sit on your butt with your hands at your sides holding yourself up- now you keep your legs together and keeping them off the ground you push legs straight out and bring them back to your chest- make sure you keep your knees together at all times

first are you trying to develop a close guard or open. If you are trying to develop a close guard you have to strenghten your legs, calves and shins. Attack the neck and arms.
For a close guard you need good hip movement and hip flexors. Talk to your instructor to learn some open guard sweeps first and drill them until you get sick and bored then do them all over again.

I am tring to get a better closed and open guard. But primarily an open guard.

we do drills in which the guy playing guard has to either sweep or submit the guy in his guard. The other guy has to pass the guard. If we do spider guard drills, the guy doing spider guard has to sweep the guy. These drills really help. Another way is when you roll, ask your partner if you can start with him already in your guard.

something I learned through observation. IN oder to pass the guard, take control of your opponents legs, in order to control someone in your guard, control him arms, especally his sleeves (for gi )