Scrape off any dried paint on the jeans. Do not blot any wet paint off the jeans. Simply remove any paint that appears dry by scrapping it with a dull object like a fingernail file.
Place the jeans under running warm water. Rinse the acrylic paint off the jeans with the warm water and use your fingers to rub the excess paint off the denim.
Place an old washcloth directly under the paint stain. You may need to place the washcloth in between the pant leg fabric.
Soak a cotton ball with rubbing alcohol. Blot the paint stain with the rubbing alcohol, and scrub the area with an abrasive sponge.
Rinse the area off one more time. Remove all the rubbing alcohol.
Follow the care label on the jeans. Wash them according to the care label and then hang them to dry on a clothesline. Avoid placing them in the dryer because any remnants of the acrylic paint that you do not see while the jeans remain wet, will become permanent once placed in the dryer.