The children loved listening to read alouds of the Otis the Tractor series that I read while we did farm related language arts activities. Here is the link to the Otis webpage so that you can find out about Otis too. There are games and videos as well as printable pages. http://www.otisthetractor.com/

The children also wanted a link to "How to Draw Otis" - I did not find one but here is a quick "How to draw a Tractor" link:  https://www.youtube.com/watch?v=bJe6SreFlS4