We don't give our children money, unless they earn it. While they do their daily chores and help around the house, it doesn't count for a job since it's something that everyone has to do in life without expectation of payment. Once we taught our children that concept, we worked on ways that they could earn money.
I know your children are older, but there is always dog-walking, cleaning up the neighbor's yard of animal waste (this is a HUGE money-maker), raking leaves, shoveling snow. Take for example, my oldest, who is very clean and organized, asked the neighbors if she could clean their baby/toddler rooms. She quickly got a few jobs lined up once word got out with how well she cleaned. Not only did she put everything away, but she put all the puzzles together, separated the blocks, etc.-she organized the rooms. One neighbor was impressed with how well she cleaned she gave her $50 for her work, instead of the agreed-upon $20 for the work.
Both of my children did odd/end jobs for the neighbors and myself that they both saved up enough money to buy a 32gb iPad Air with 4-year warranty. If you are in the market for an Apple, you know those suckers aren't cheap! My oldest was able to buy her ipad within 6 months of setting out to buy one and my middle was able to get hers within 8 months since she was limited on the higher-paying jobs, such as babysitting.
Another way they can earn money is by babysitting or co-babysitting (depending on age). Last year, my oldest was the neighborhood babysitter-everyone came to her each weekend. We did a neighborhood block party and all the neighbors pitched in to pay my daughter, the yard guard, for her babysitting services. In one night, she watched 19 children (of course the parents were in the next yard), but she earned over $200 for that night of playing with children--something she already loves to do! We have since moved to the country and there aren't any babies to babysit--it is killing my daughter and she can't wait until we move back on a military base where there will be more children and more babysitting jobs!
I guess what I'm trying to say is that not just Mom & Dad are the only people to give them money for work done. Other people don't mind paying children to do jobs, provided they are responsible enough to do said jobs. My parents often helped out and gave my children jobs to do that they would pay them, granted not as much as they should, but they did pay for them work done. I don't know, I guess we took the approach that if you want money, you have to work for it, because when you are older, no one is going to hand you money over without working for it. So perhaps we are using this as a teaching example of learning how to work for your money. I don't know, but it's something we have been doing for several years and seems to help with our girls earning money. Since we've started doing this instead of a weekly allowance, they have each bought an iPad, but have also put over $1,000 in to their savings, after they gave 10% of their earnings in tithe to our local church and kept 30% for spending.
You will find what works for you and your children. Sometimes it just takes trial and error. Good luck! I can't wait to see what you come up for your children to earn some pocket money!