Big Sandy Independent School District (Polk County, Texas)  Big Sandy Independent School District is a public school district based in the community of Dallardsville, Texas (USA). The district consists of one school serving all grades. As of the 2010–2011 school year, the appraised valuation of property in the district was $278,305,000. The maintenance tax rate was $0.104 and the bond tax rate was $0.016 per $100 of appraised valuation. In 2011, the school district was rated "academically acceptable" by the Texas Education Agency.