Set Up One Cash Point. For any event, take cash at one place only. The fewer hands that touch it, the better. For the spring carnival, don’t have people pay a quarter at each booth. Have them purchase tickets from a cashier. It’s great to have volunteers help children at the holiday shop. But have the kids walk up to the cashier to pay; don’t have them pay the helpers.

Create a Paper Trail. Always use paper receipts for cash transactions. This information is key in creating a budget, you should have it for the IRS, and it’s smart policy to keep records to control your finances. You may make an exception for the carnival, where you are taking in a small amount of money many times over. But in this case you should tally each sale. At the end of the day, the number of tallies should match your cash receipts and it should match the number of tickets taken at each booth.

It Takes Two. Always have two people present whenever cash is around. Make it a rule that two people tend the cash box at all times, even if it’s only a one-person job. Likewise, always have a least two people on hand when cash receipts are counted. After the cash is counted, have the counters each initial a form certifying how much money is being turned over to the treasurer.

Make Deposits Immediately. Never let cash—or any receipts—sit for a few days. Receipts should be deposited as soon as they’re counted, certified, and turned over to the treasurer. If your event is at night, lock the money in the school safe and deposit it in the morning.

Keep It Simple. Never take IOUs. Tell people who say they’ll pay later that you can’t let them—PTO rules. Never mingle parent group money with your own. Don’t ever, for example, deposit PTO money in your account, then write a check to the group for the same amount. Among other things, this is a good way to get in trouble with the IRS. And never float a loan to the group, then take the money out of cash receipts as repayment.