Thank you for using the Jiskha Homework Help Forum. Even thought the first one is for kindergarten you never know where you might get ideas!
1. http://www.lessonplanspage.com/SSTransportationLandAirWaterK.htm (the idea could be some visual stimulus = movie, ads?)
2. (part II of #1): http://www.lessonplanspage.com/SSCommunityTransportationK.htm
3. (PDF file to download. Look at the activities; students might study various makes/types of land vehicles?): http://www.lessonplanspage.com/SSCommunityTransportationK.htm
Don't be afraid to brainstorm and use your imagination! You might even record the "horns" of various vehicles to have students "guess" which vehicle it's from???