Suggestions for trying out environmental or transportation planning?

[starusjack]

I already have my bachelor's degree in computer science and mathematics. I haven't found anything that particularly interests me and I want to change fields. Both transportation and environmental planning sound interesting to me, but most positions require education in the field. I'm willing to go to graduate school, but I want to make sure I like the field before I do.

Any suggestions on how I can test the waters? I'm in the Los Angeles area if that helps for specific programs or companies.