If the reason you don’t have money is because you are learing, I think it is important that your kids shouldn’t feel like they are deprived because you are learning.
Now, I don’t doubt that the better way would be to teach them to understand that learning is more important than money, and I am sure some posters will say that. Yet, if that does not come across properly- and in many cases it won’t- your kids will come to resent learning because of it.
So, I would say, make a super effort to find the money for your kids mishigasen so that they will appreciate learning.