1. American family Day
2. National coloring book Day 
3. National watermelon Day  
4. National chocolate chip cookie Day  
5. National oyster Day 
6. National root beer float Day  
7. Purple heart Day  
8. International cat Day 
9. National book lovers Day  
10. National s’mores Day 
11. National son and daughter Day 
12. Middle child Day 
13. National left handers Day  
14. Comic book Day 
15. National relaxation Day 
16. Discovery Day   
17. Black cat appreciation Day  
18. National fajita Day  
19. National potato Day   
20. National chocolate pecan pie Day 
21. National senior citizens Day 
22. Take your cat to the vet Day 
23. National sponge cake Day 
24. Kobe Bryant Day 
25. Banana split Day  
26. National dog Day 
27. National just because Day 
28. Cherry turnover Day 
29. National lemon juice Day  
30. National beach Day 
31. Eat outside Day

Cites:https://nationaltoday.com/august-holidays/