As they travelled north, she asked him if she could call at the Karitane playcentre to pick up her twin 2-year-olds, then she would drop him in Waikouaiti. He said that was fine.
"It was one of those days I forgot to take my keys - I never thought anything bad would happen."
When she and her children got back to the car: "It was like a dream; it was gone."
She ran back to the playcentre and asked a teacher to phone police. One of the teachers gave her a ride home.
The car was returned after police apprehended the youth near Weston later that day.
Missing was her handbag, which had her driver's licence, credit card and other items "women carry in their big bags".
Sergeant Tony Woodbridge, of Oamaru, described the youth as "a mini crime wave".
He said police saw the youth driving the woman's car in District Rd, between Oamaru and Weston, about 7.20pm on Wednesday.
On the drive to Oamaru, the teenager threw out two child seats and a handbag from the car, Mr Woodbridge said.
The child seats were recovered at Shag Point, but police were appealing to anyone who found items, including a mobile phone, a handbag and its contents, on
State Highway 1 between Waikouaiti and Oamaru to contact them.
A 16-year-old Oamaru youth was remanded without plea from the Dunedin Youth Court to appear in Oamaru Youth Court next week.
He was also charged with the theft of tobacco on Wednesday, theft of tobacco from another Dunedin shop on November 9 and driving off without paying from an Oamaru service station on November 10.
