Could be several issues. Meanwhile, I know this is very frustrating!!!
1. Mid-life crisis? He does not want to do "grown-up" planning, because it sounds so very responsible. He wants to have the sexy red midlife crisis motorcycle, and recapture youth, instead of facing adult future responsibilities.
2. He can't think that far ahead, something more immediate is bothering him. Job insecurity? Financial worry? can't plan if you are afraid of the future.
3. Depression? He cannot think ahead, because with depression you cannot THINK. Get counseling etc. for depression.
4. Intimidated because you might want to change status quo? May be depression, could be other things.
Action:
1. If above fit, then address accordingly.
2. "Honey, I have decided to go full-time to school, so I can finish sooner, and earn money. If I do, I need your help to cover 3 nights a week while I take the XYZ class next quarter. Can you do this?" You plan, you foresee what he would need to do to accommodate this, you ask if he can do it. Then, move forward. Start with small steps. Take turns accomplishing goals - what would you like to do next, honey? If he sees that you are starting to solve the future questions yourself, while involving him in support, then maybe he will get on board.
3. All work and no play..... Plan a fun vacation together. Not a 3 week tour of Europe, just out-of-town. reconnect as People, not just Mom & Dad. I used to "kidnap" my husband - tell him to clear his schedule for a certain evening, I picked him up at work, then I had the activities planned. Once, it was a concert. Could be just picnic barefoot in the park, watching the stars come out. Bottle of sparkling cider (no liquor in city parks), finger food, gourmet dessert. Music, blanket. Low cost, but break up the routine.
Family activity: "popcorn fight" - too cold for snowballs, pop a batch of cheap unflavored unbuttered popcorn, throw popcorn at each other! Leave it for the birds! No clean up! Just don't do it before rain is expected!
Beach night picnic on the living room floor! Break up the routines! Then get him involved, and have some future discussions later. Don't tie the discussions to the fun party, he will be too suspicious and resistant. Just have fun together. Move yourself ahead, tell him what you need from him before you leap, then start.
good luck!