There is another factor to consider. You may be unable to concentrate because nothing interests you. I had absolutely no interest in intellectual pursuits in high school. It wasn't until a year or more into my Bible college experience that my intellectual light turned on. I've given a fair amount of thought to why this occurred. My current view is that I just had bad teachers in high school. They couldn't teach me to swim because their own intellectual pond was too shallow.
If you want to be a lawyer you are going to need to study Political Science, Philosophy, Intellectual History or a similar field. You may find it useful to go to your local college, read the student evaluations produced by the student government, talk to students and find the best professor in one of those fields and sign up for her or his class. A good professor in one of those fields should spur your interests and assign challenging enough work that the combination might solve the concentration problem.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13