Does anyone know if a BA in business administration (such as management, office work) would earn more than an elementary teacher?
Also if a person received full finanical aid for an associates degree, could they receive it for a bachelors?

In general, starting in a job that requires you to have a B.A. in business administration is more likely going to earn you more money than an elementary teacher who is just starting. But, some school districts do pay very well. And, what type of job that you have and who you work for is going to make a big difference as far as what you are going to make in a job that involves business administration of some kind.

Other things to be considered would be insurance and benefits packages.

Yes, you could receive full financial aid in order to go for a bachelor's degree. It depends on your circumstances and where you go to school.