The siblings left their home in Madison Drive yesterday (29 May) at about 8am.
The pair were due to catch a bus to Pacific Werribee, where Shenae had a work placement and Brodie was to attend school in Tarneit.
Neither attended their destinations and have not been seen since.
Shenae has an intellectual disability and is Caucasian in appearance, with a solid build and blonde shoulder length hair that is usually tied in a ponytail.
She is believed to be in possession of a pink Nike backpack.
Brodie is Caucasian in appearance, with a slim build and short and scruffy brown hair.
He is believed to be in possession of a black scooter and a black backpack.
The pair are known to frequent Werribee and the Wyndham area, Caroline Springs and Ballarat.
Police have released images of the teens in the hope someone recognises them and can provide information regarding their current whereabouts.
Anyone with information about Shenae and Brodie is asked to contact Werribee Police Station on 9742 9444.
