For grandparents hosting children on spring break or planning a camp for summer, here are a few tips from Joan Brackin and Georgia Witkin, senior editor of Grandparents.com and a professor of psychiatry at Mount Sinai School of Medicine in New York:

• Open the camp to the older children. Brackin welcomes all of her grandchildren who are out of diapers.

Once they reach 13, they become her "counselors in training" and help care for the younger ones. Brackin said the high-schoolers help maintain a well-supervised environment; for safety reasons, other grandparents will want to limit camps to a smaller number of children.

• Keep projects geared to subjects that interest you as well.

• Keep activities short; always plan more activities than you think time will allow.

• If you're doing something new, tell the children about it ahead of time, Witkin said. "You tend to get a little more excitement and a little more control."

• Don't forget rewards. "Some grandparents think it's bribery, but I'm here to say it's an important education tool," Witkin said. "Think of it as recognition, not payoff."

A reward can be something the children were going to do anyway, such as choosing dessert.