We went with 2 trains of thought. One was that each kid had the same amount of chores as how many years on the planet and each chore is worth $1.00 a week, and then we incorporated Dave Ramsey's saving/spending kids program into that. He suggests that they give 10% to charity (or tithe), 30% goes into long-term savings (their car), 30% goes into short term savings (I wanna buy a Webkinz or some other treat) and then the other 30% goes to immediate spending.
DD6 does 6 chores a week, some she is responsible for every day some are once a week:
1. Make bed (every morning)
2. Tidy up room (every night)
3. Wipe up bathroom counter (every night-the kids and their toothpaste, oy vey!)
4. Feed cats every day
5. Organize the shoe shelf (once a week)
6. Empty all of the small garbages (once a week).
DD10 does 10 chores a week:
1. Make bed (every morning)
2. Tidy up room (every night)
3. Wipe up bathroom counter (every night)
4. Vacuum (once a week)
5. Swiffer all TVs and dvd players (once a week)
6. Take out garbage (as needed-usually 2-3 times a week)
7. Unload dishwasher (every day)
8. Fold towels (1-2 times a week)
9. Fold socks (once a week)
10. Put her own clothes away (as needed)
DD6 gets $6 every week and puts $0.60 in her charity jar, $1.80 in her long term savings, $1.80 in her short term savings, and $1.80 in her immediate spending.
DD10 gets $10 every week and puts $1.00 in charity jar, $3.00 in long term, $3 in short term and $3 in spending.
They hardly ever use their immediate spending so they usually just end up throwing it in their short term spending. They are only allowed to buy one edible treat and only with permission (everyone in my house has a severe sugar obsession, LOL). Other than that it is fair game. DD6 just spent $24 at Justice on a Webkinz and some fingernail polish (she's lucky, because even though she gets so little compared to DD10, she keeps losing teeth and then throws that money in her short term savings, HAHAHAHA!)
I made a spreadsheet of each girls chores along with the days of the week at the top, then had it laminated and I have it on the front door. Every day I mark their chores off (or mark that I didn't need them to do certain ones that day) with a dry erase marker.
So, that's what we do. DD10s' 2 bff's don't do chores or get an allowance, they just get money. I don't know about DD6s' friends. DH and I are soooo terrible with money, we are really hoping to instill some money smarts into these two. And if they grumble (DD10!) then I say, you can do your chores without complaining and get paid or you can complain all you want while you do your chores and get nada, but these are things you are responsible for. Usually gets her to close her mouth.
Hope that helps!