What classes should I take?

Ok so I can't decide on what classes to take. There are a set that I'm definitely taking, and then there are the many many that I sorta maybe want to take but don't want to make too much work for myself.

I am definitely doing Design Team leader, Robots Sensors & Actuators(RSA), and SBE3 (Systems Bioengineering 3). They are 4, 3, and 4 credits respectively.

Design Team Leader: I'm a dteam leader. It takes up time and energy. Yay.

RSA: Lab based course. 1 lab session, 1 prelab, 1 (3 hr) lecture, 1 lab report. Per week. Should learn a lot of practical hands-on knowledge and exp. Looking forward to it.

SBE3: Homeworks each week. Rumored to be easier than SBE1 and SBE2. Moderate amount of work.

The other classes I'm interested in are: Number Theory, Leading Change, Data Structures, Linear Dynamical Systems, Control Systems, and that's all.

Number Theory: can't understand what the professor's saying. Not taking that class.

Leading Change: No distribution credits, though he tells us it's a writing credit, not that I need it. A good bit of reading, researching and writing, and slightly project-y. Seminar-style, the prof is nice and there is a lot I could learn. But it may turn out to be more work that I bargained for.

Data Structures: intermediate level programming course. Taught in java. Good prof, but class is not needed for my major. Would also be a fair amount of work in terms of coding projects and such.

Linear Dynamical Systems: graduate level course (apparently) which is mostly advanced linear algebra and its meanings. Probably don't want to do this.

Control Systems: counts for my major, rather small class size though. A more detailed learning of some material I've already learned.

So I can do up to 2 more classes than the 3 that I'm definitely taking. So far it seems like it's going to be leading change and control systems, but leading change might turn into data structures or just get dropped. We'll see. Not terribly into the high credit count thing. If I do those 5 classes, I'll have 17, and if I drop leading change, it comes down to 14. Either way it works. Hopefully Control Systems is manageable. First homework is due next Thursday.

What should I do?