I went to law school in my 20s. I had no kids. No DH. I was free to spend a lot of time concentrating on my course work and I needed to do that. The school I went to strongly recommended their students not work at a part-time job during the year. I can see why. For me, the first year of law school was the toughest. I had been a very good student in college, but law school was a whole different ball game. Everyone was so smart. The teachers had such high expectations. There was actually a time in my first semester when I considered dropping out because I was overwhelmed by all the reading, the teaching methodology and course work, but my then boyfriend (now DH) convinced me to think twice. I stuck it out. I graduated and passed the bar.
I think you have to look at the cost, time commitment, and impact on your current lifestyle. At 38, you're not "too old" to go to law school. I had classmates that were far older than you. They were some of the best and most interesting students because they had real world experience compared to people like me who came to law school straight out of college.
It sounds like you're not planning to work for a private firm. It sounds like you're thinking of working in the education system or maybe for nonprofit. If that's the case then you're not competing with too many young hot-shot 20-somethings just out of law school. After graduation, most of my friends headed straight for large private firms because that where the big bucks were back in the day.
Could you do what you want to do (policy and running of schools) without a law degree? Could you do that with a Masters in Public Administration or Masters in Public Affairs? There are some schools that offer a JD/MPA.
I think a law degree is very useful even if you choose not to practice law directly. I know several people who were hired for government positions - management and policy - because of their law degrees. They don't represent clients or litigate, but their legal training landed them those jobs.
Ok, I rambled on a bit here.

I hope there's something useful to your query.