August monthly designations

American Adventures Month
American Artists Appreciation Month
Native American Heritage Month  (See also November)
American History Essay Contest (8/1 – 12/15) 
Arrr-gust: International Pirate Month
Black Business Month
Boomers Making A Difference Month
Bystander Awareness Month
Children's Eye Health & Safety Month
Child Support Awareness Month
Children's Vision & Learning Month
Get Ready for Kindergarten Month
Happiness Happens Month
Motor Sports Awareness Month
National Breastfeeding Month
National Catfish Month
National Crayon Collection Month 
National Goat Cheese Month
National Immunization Awareness Month
National Panini Month
National Minority Donor Awareness Month
National Read A Romance Month
National Spinal Muscular Atrophy Awareness Month
National Traffic Awareness Month
National Truancy Prevention Month
National Water Quality Month
National Win With Civility Month
Neurosurgery Outreach Month
Psoriasis Awareness Month
Read A Romance Novel Month
Rye Month
Shop Online For Groceries Month
Tomboy Tools Month
What Will Be Your Legacy Month
World Mutt-i-grees Rescue Month

Source: Brownielocks & the Three Bears; Days of the Year, Checkiday, and other obscure holiday sources.