It is a great idea to be teaching kids this at a young age to be responsible with money and to teach them budgeting.

Is it too early? Never! Start off how you do it yourself. Far too many people do not know how to budget before they head off for collage/university.

1) Establish the fact that chores are expected and not paid for, but then offer a choice of chores that can earn money. Example: making their own bed, as messy as it is is their own space = no pay

2) Pick up their own laundry, toys. = no pay

3) Empty dishwasher = paid

4) Tidy up mud room / shoes are at door way = paid

Next once you have establish the pocket money, you will need 3 jars.
1) TAX
2) Savings
3) Free Spending

Tax needs to be explained weekly so they understand it, you can decide ahead of time what to make of that money afterwards (a suggestion would be to donate it).