Throwing more money at schools is not going to solve any of those problems. There are people that have had fewer resources, less access to information, and even were discouraged from learning, yet they excelled anyway because they were determined to learn and found ways to do it. If you value education, if you get kids to realize the value of education, you'll find a way to make it work even with limited resources. If you can't get people to value education, if you can't get kids to realize the value of education, it won't matter how many resources you have.
That there are also cultural variables working against education is undeniable. Can you find examples of people from impoverished backgrounds who still got themselves a good education? Sure! But does that mean that money is completely irrelevant? No!
There are some students who could find ways to educate themselves if they wanted to. But that's a small minority, and we can't easily inculcate better values into everyone rapidly enough to change that part of the puzzle. Such a paradigm shift tends, by its nature, to be gradual.
Most students need the guidance of a good teacher--or teachers at the secondary level. That's why teacher quality repeatedly comes up in studies as the most significant variable schools can control. A lot of people, consciously or unconsciously, want teachers to all be self-sacrificing saints who will soldier on regardless of their personal financial status. And it's certainly true that most people who become teachers aren't doing it to become rich.

. But surprisingly, most teachers do feel the need to consider their own financial situation.
One of the effects of inadequate funding is stagnating salary levels, which in turn result in fewer people going into teaching. When I first got my credential, states like California had an excess of teachers. That rapidly became a deficit within a few years. Quality took a hit as well. I can remember a colleague and I comparing notes a long time ago. When we were in high school, a fairly large number of people were interested in careers in teaching, including some of the strongest students. Flash forward a couple of decades, and few of our own students were interested--and often they were among the academically weakest. That's not to say that those are the only people left in the teaching pool by any means. There are a few saints, plus people whose spouses are the primary breadwinners and people who are single and childless (like me). But it does illustrate that teacher compensation in many areas is a factor impeding teacher recruitment.
Figures vary, but it appears we have 55,000 open positions and around 400,000 staffed by unqualified or underqualified teachers. Guess where these issues are the most acute? That's right--schools with less money to spend. And who gets the best teachers in the pool? Generally, schools with the most money to spend.
Even places like California, which got away from the reliance on local property taxes (by having the education portion of the tax paid to the state, which then redistributes it), haven't really solved the issues of inequality. That's partially because the formula takes into account cost of living in the different areas on the assumption that school employees either need to live nearby or have commuting expenses. There is truth in that, but it somewhat perpetuates the pattern that schools in affluent areas (with high housing costs) get more money. Also, most districts have education foundations to raise donations, but their success is largely a function of how affluent their community is. And there are also various ways for city governments (who are still funded by local property taxes) to legally funnel some of their money into the local school districts.
I don't blame the more affluent for wanting the best they can get for their children. Any parent wants that. But in the current climate, where budgeting is basically a zero-sum game, every dollar that goes one place takes a dollar away from another. That means any attempt to equalize educational spending is met by opposition from people who can better afford to donate to political campaigns, have the time to be politically active, and vote at a much higher percentage rate. And the worst part? We probably should be spending more money on students in poverty to try to reduce existing gaps.
One other issue needs to be addressed--the disparity between teacher responsibility and teacher pay. Back in the day, teachers were primarily dispensers of information and coaches for skill practice. Naturally, those responsibilities still exist. But today's teachers are also expected to be psychologists, social workers, nutritionists, first-aid providers, emergency responders, surrogate parents (in extreme cases), and (in schools who think the best security plan is to give all the teachers guns) expert marksmen. In other words, teachers are expected to fill any gap in the lives of students or the functioning of the school that comes up. If a student is having any kind of problem, even if it's not caused by the school, teachers are expected to fix it. (And at least in California, in the event of a disaster like an earthquake, teachers are expected to stay with their students until every single one is claimed by a parent--whether the process takes hours or even days. That means teachers have to make emergency plans for their families in the event that the teacher is trapped at school.) Yet as responsibilities increase, pay does not increase in a commensurate way.
A typical teacher contract pays on the basis of a seven and a half hour day. Two separate national studies have shown that the typical teacher work day is ten hours, the difference being grading, preparation, parent conferences, student conferences, etc. And that doesn't even count days on the weekend. At the peak of my career, I was doing 10-12 on weekdays and 4-5 on Saturday and Sunday. In other words, I was doing a 58-70 hour work week and getting paid for a 37.5 hour week. Oh, and then there was the all the time I spent, mostly during winter break, writing college recommendations, or the time I spent during summer prepping for the new school year. Call me crazy. (People did, even at the time.) I don't regret doing it, and if I could go back in time, I wouldn't change my career choice. But when a community member said that teachers just needed to put more effort into the job, I described my typical day and added, "There's no such thing as more."
Do all teachers work that hard? Of course not. Some do the bare minimum. But if the average is a ten hour day, you've got to figure that the slackers have to be fewer in number than the workers. The prevalence of stress-related illnesses among teachers is also an indicator. And in my own English department, there were a high number of divorces, one full nervous breakdown and some partials. I never broke down completely, and I dodged the divorce because I never married in the first place. But I did gain an understanding of why education in medieval Europe was mostly handled by monks.

I'm sorry for the avalanche of detail. But it's the kind of thing that, if you haven't taught, you aren't going to realize. Even I didn't realize what teaching was like until I did it. (I actually thought I could teach during the year and write during the summer. LOL. That didn't happen except for the very first summer and the three at the very end.

So no, money isn't the solution to every educational problem. Sadly, there are many contributing factors, and just having more money doesn't necessarily produce a better result if the money isn't spent wisely. But not having the funds to encourage people to go into teaching and compensate them a bit more like they should be is certainly part of the problem.