Arquette, 36, took his little girl to Mr. Bones Pumpkin Patch in West Hollywood for a day of face-painting and fun on Sunday.
"David and Coco had a great time together at the pumpkin patch. Coco had her face painted like a cat and she looked adorable," an observer tells PEOPLE. "She also seemed happy about spending time with her dad. David looked great and was in a wonderful mood as well."
Coco, 6, participated in several activities, including a ride on the super slide and a stroll through the straw maze.
"David was very sweet and patient with Coco," the observer says. Even when the valet mixed up several car keys and tried to give Arquette the wrong car, "he stayed calm and still gave a great tip," the source adds.
Party with PalsThe day out with Coco came after a night of partying for Arquette, who attended a birthday party for 90210 costars Jessica Stroup, 24, Shenae Grimes, 21, who has a cameo performance in Scream 4 with Arquette.
The bash featured a sneak peak performance of the vaudeville-inspired show, David Arquette Presents Beacher's Madhouse, sponsored by Samsung Galaxy at the Hollywood Roosevelt Hotel.
"David was in great spirits, with an ear-to-ear grin all night long," says a source. "He was spotted dancing much of the night – at times even on stage with the performers," which included giant bunnies, panda bears and burlesque dancers.