Have you tried Insecticidal Soap? 1 teaspoon of a real soap (Ivory, Fels Naptha, Dr. Bronners, or about any other Castile soap) in 1 quart of water, or a commercial Insecticidal soap is one place to start.

I have those, too! They are driving me crazy, but I have not been able to identify them yet.

i haven't tried anything yet. but i may start with the insecticidal soap. after doing some digging on the internet i think i've determined they are flea beetles. my neighbor said he had them on his lettuce earlier this year and used some sort of insecticide and they haven't returned. they probably just hopped across the street to my garden. LOL

Spraying "some kind" of insecticide can be worse than doing nothing because the broad spectrum poisons sold off the shelf will not only kill the pest but will kill the beneficial insects that may be helping control those pests, and will also kill the pollinators and the food source of the birds we have around us.