Start with the Simple Motorized Machine set Green Instructions D5 without the stand.
Turn it around, and add wheels.
Add a place for front wheels and use connectors that are axles on one side.
Add front wheels and places for the rubberband to attach.
Now you are ready for the Chocolate Kiss contest.
Pull back car using Cities and Transportation sets
Pull back car with blue sets
Example Pages
http://www.marshall.edu/LEGO/VOB0708/28Feb08VoB/28Feb08VoB.html
http://www.marshall.edu/LEGO/VOB1011/2011-02-14VoB2/2011-02-14VoB2.html
http://www.marshall.edu/LEGO/VOB1112/2012-02-21VoB3T/2012-02-21VoB3T.html
http://www.marshall.edu/LEGO/Playmates/12Mar08Playmates/12Mar08Playmates.html
http://www.marshall.edu/LEGO/Culloden0708/22Feb08Ckiss/22Feb08Ckiss.html
http://www.marshall.edu/LEGO/CCE0708/26Feb08CCE/26Feb08CCE.html
http://www.marshall.edu/LEGO/21st0809/26Feb0921st/26Feb0921st.html
http://www.marshall.edu/lego/lessonplans/RubberBandCarLinks.html
