I was just asked by a local school how to make a post always appear on the home page – the answer is surprisingly simple, but if you don’t know where to look its rather difficult to find!
On the publish box to the right of the wordpress post in the editor, click on the Edit link next to Visibility: Public and then tick the Stick this post to the front page box.
Done! The post now stays at the top of the front/home page. All you have to remember to do is to un-stick it in the future!