I think it would be a good idea, have it announced over school announcements(if you have them), put it in the neighborhood/city newspaper about it and have a small fee, but probably mention that it is free to get in to the competion.
Don't forget about Dean's Homework Assignment
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Who let the Blue Smoke Out
Team 2194 Mentor - 2012-Present -
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Team 2207 Alumni -
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Iowa
FIRST LEGO League Planning Team Member - 2010-Present -
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FIRST LEGO League volunteer - 2008-Present
2008: MN Regional Quarterfinalists, Website Excellence
2009: MN North Star Quarterfinalists, recognized for safety, Website Excellence