I'm going to be starting college for computer science in a couple months and don't know which language to pick up between now and then. I'm fairly strong when it comes to Java, and I'm fair with C++ and Visual Basic. So, any recommendations?

Try python

See what languages your university/college offers. And if you have to take the basic computer science classes, see what languages are taught in them. Get a head start on it. For example, mine started with JS, so I began working with it.

As you know Visual Basic, upgrade that and dive into c# and asp.net

I would suggest any functional programming language. It may not be your choice for production code, but will make you realize things about primitive recursion and loops, about tail recursion and if it is a pure language, like Haskell, it will actually help you grasp some concepts of computer science, like type theory, logic and category theory (after all "a monad is just a monoid in the category of endofunctors"). Also concepts like Curry-Howard correspondence or Church-Turing thesis will be a lot more clear after studying functional programming.
Furthermore languages like OCaml will give you a good head scratch, until you make the connection between Object Oriented and Functional programming.
I believe that if you do follow my advice you will be able to understand a lot more stuff of other multiparadigm languages, like JS, Python and even Java8 and even use them more efficient.
That is my advice as a fellow student.

An idea of what you wanna do later/where you wanna work?
What do you want to accomplish? An educational goal, (then go, as already told, for functional programming. - you will most likly never learn that "one the job".)
The 'more correct way' then go c/c++ and understand what your doing. This will help very much in understanding c#(/Java) and making good use of it.
This also goes if you want to go for Desktop (windows/Linux) or embedded (though here more c and unoptimised compiler in c)

If you want to go into Web: ofc js/php etc

For the kind of "PC here is number do something with it" like a mathematic would do it - go for python.

Data science same. Python and r are great things for math/Maschine learning and straight forward solutions.

Of you already know c++, get better with it as c# builds upon it, and you will have a wider range.

But never forget :language is a tool.
In computer science you learn how to use it correctly, so don't worry too much about it ;)