This is a personal budget spreadsheet that I created which completes automatically calculations. I use it for my Senior Economics course, but it could easily be adapted for all grade levels and classes (life skills, mathematics, etc.).
I have students search and select a job listing in the career field they wish to pursue. With the spreadsheet, they must breakdown how much they will make each month after taxes and figure out their budget expenses first for a month and then for a year. I have 37 separate subcategories in the spreadsheet which will make automatic deductions when students input the expenses.
It will also project a yearly end balance (which most students are surprised ends up being in the negatives, meaning they spent more money than they made... a very valuable lesson for teenagers!). It's a great project.
It is also the spreadsheet budget that I use in my personal life, as I find it very effective in keeping track of my monthly spending habits.