Tashlich at the lake at Rosh Hashanah
We all make mistakes. One very important life skill is to learn how to deal with them. Decide which one you want to embrace and take it with you to the next year, meaning you don't mind repeating it again, and which one you'd like to leave behind.
Take the family out for an outdoor Tashlich activity
Take very small pieces of paper, degradable toilet paper is best, and sit down with your kids to fill their pockets with mistakes. Take the family to a close by lake, or the beach, a small pool will do (even thought it's not according to tradition), and then empty the pockets of the ones you want to let go, and keep the ones you want to keep.