WATCH: 4-year-olds celebrate their Graduation Day

SEATTLE -- It was Graduation Day for 4-year-old kids, complete with caps and gowns.

These children were enrolled in King County's Parent-Child Home Program -- a preview of things to come as the county's "Best Start for Kids" initiative was passed by voters last fall.

One mom says her son's early schooling is really inspiring him to learn. "His vocabulary has increased immensely. He has me running to the dictionary at times, saying, 'What did you just say?'"

King County Executive Dow Constantine said the six-year, $400 million levy will help thousands of young children achieve their full potential.

"I'm so glad that we have a program that's going to help every parent in the community," Constantine said.