Can a Theory Become a Law?

No, a theory and a law have two separate agendas and are not directly connected as most people believe.

The first problem within scientific understanding is the misunderstanding of the word theory. In common usage we refer to theory as a guess or conjecture, however, that is a slightly wrong outlook when applied to scientific theory. A theory explains why things are the way they are.

I found a good definition for it use-

"a proposed explanation whose status is still conjectural, in contrast to well-established propositions that are regarded as reporting matters of actual fact" (dictionary.reference.)

That means that a theory is still a "guess", but one based on facts. So, here is the kicker. There is NOTHING above a theory. A theory is what you ultimately strive for when it comes  to explaining things.

A law on the other hand describes the universe. Lets take a example:

First lets take Boyle's Law- (Wiki Definition) 

is one of many gas laws and a special case of the ideal gas law. Boyle's law describes the inversely proportional relationship between the absolute pressure and volume of a gas, if the temperature is kept constant within a closed system.

  Boyle's law describes and observation of a explicit event however it does not conclude the explanation for why it happens.

So, in essence, they both can work together to give a complete understanding, but a theory is NOT a unproven law. Its a very important concept to grasp whilst arguing idea changers such as evolution. It is a true statement to say that evolution is a/only a theory, but in most cases people are referring to the common usage and that is not right.

Theory- Explanation based on facts and it can be proven wrong however it is our best understanding for the why.

A theory cannot become a law nor a law a theory