Career change or possible pathways?

Hi,

I recently graduated last spring from a university with two bachelors in earth science and physical science. I have been working for staffing and temp agencies since then. I realized, however, that the skills I have gained over the past year has not aided me. I recently got let go from a position because my skills were lacking. The jobs I have taken were GIS based. But working these jobs has not made me happy or satisfied. My passion has long been in Physical Science. I changed to a more economical profession because of the economy.

I am now unemployed and thinking about my career and where I want to go. I am 25 years old. The thought of going back to school is looking like a enticing option, but I graduated with a 2.8GPA in undergrad. My dream and plan has always been to go into physical sciences and become a professor or researcher. I feel like a career change is out of the cards due to my recent jobs, GPA, and age.

Thank you in advance for any replies.