I think the problem has more to do with earning or handling money. If your mom is in a low paying job, perhaps you could get a part time job to help, you two can try and look for a better one, or she finds a part time job [while tiring some people have to] if it's a matter of overspending and not budgeting, there are options there as well. Budget every single cent, even if you have a remainder after the bills, put them in categories [such as savings and entertainment] another trick that really helps is only spend cash and eliminate your debit and credit cards so you're not tempted to buy more than you could afford.
In terms of spells I would look into a charm or honey jar. Something to attract money to you for a long period of time.
If the link doesn't work you can find it in my history. It's titled 'Money Jar Spell' and it's suppose to attract money. [Though since Canada doesn't have the penny anymore you could either ask at the bank or just add an extra coin of each]