Zucchini- theres a little bud there it's just hard to see.
Tomato- I know you can't see the teeny tiny bud on this one but I promise it was there, or a really green piece of dirt but I'm going to stick with a tomato plant is growing.
Spinach- Nope that's not grass, that's spinach growing.
Watermelon- Those would be watermelon buds coming up.
I hope that I will be able to get out and take some updated pictures of the garden today. There is no rain forecast and the garden has been getting a nice dose of water the past few days. I'm excited to see if there has been any progress.