All pupils at the trust’s schools in Selsey, Bognor Regis, Rustington, Littlehampton, East Preston and Worthing were invited to take part and more then 250 entries were received.
Chris Seaton, chief executive, wanted a fun and festive design and winner George Browning came up with the perfect picture, a cheeky reindeer nibbling away at a Christmas tree while a shocked Santa looks on.
George, a year-six pupil from Canada Class at Rustington Community Primary School, won a Royal & Langnickel art and easel set for himself and £100 for his school to spend on art supplies.
Mr Seaton, who presented George with his prize, said: “This competition was a great way to get all of our children involved in a fun, artistic activity.
“We challenged the children to create a bright, bold card and it was wonderful to see the entries coming in. The team of judges, myself included, really enjoyed working our way through the shortlist from each school.
“The creativity was very impressive, so a huge thanks to every child who entered the competition.”
Schoolsworks was established in 2012 and its schools are Medmerry Primary in Selsey, Rose Green Junior and Edward Bryant in Bognor Regis, River Beach Primary in Littlehampton, Rustington Community Primary, East Preston Junior and Downsbrook Primary and Whytemead Primary in Worthing.