Squash plants?

Hi Teresa, that looks like powdery mildew. You can spray the leaves with a mixture of 2-3 tablespoons of common apple cider vinegar, containing 5% acetic acid mixed with a gallon of water.

It looks like bacterial leaf spot infection. To be sure, take your pictures to your local nursery for identification. You might also want to contact your cooperative extension with master gardeners.

https://extension.okstate.edu/fact-sheets/pumpkin-and-squash-diseases.html

Since it's the edges of the leaves, it may be a watering problem. Squash need 1 inch of water per week. The soil should be moist up to a foot below the plant.

It looks as though they may not be getting enough water. Remove a few of the worst leaves and take to a local nursery for advice.

Perhaps too much water. I would go with the spray Michelle recommended.

Take a picture and send it to your local master gardners. They are great at plant identification.

Hello, hope this helps you out, it covers a lot of squash issues,

https://www.youtube.com/watch?v=BZt6iEapuE4

They look pretty healthy, maybe they are too crowded?

Yes, I didn't expect them to get so large so quick. I only fertilized 1x with low nitro. Thx

I wonder too if it's getting enough water. Squash plants need a fair bit of water