Have local businesses hold "shorts day" or "jean day" where the employees have to donate $5 to the playground construction fund (or any determined amount) every time they wear either shorts or jeans to work.
Ask the business owner or manager to serve on your committee or assist with fundraising efforts.
See if you can get in-kind services like free use of copiers, computers or phones. They may be able to provide similar services and materials for different activities throughout your planning process.
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