Watermelons!
Summer is great for seasonal fruits, and this summer, I’ve been eating a lot of delicious watermelon. It’s tasty, and cool and refreshing. 
According to the National Watermelon Promotion Board, it’s easy to choose a good one at the store:
It’s as easy as 1, 2, 3.
1. Look the watermelon over.
You are looking for a firm, symmetrical watermelon that is free from bruises, cuts or dents.
2. Lift it up.
The watermelon should be heavy for it’s size. Watermelon is 92% water, most of the weight is water.
3. Turn it over.
The underside of the watermelon should have a creamy yellow spot from where it sat on the ground and
ripened in the sun.
Don’t forget to “knock” on the watermelon–a good, resonant sound means it’s ripe–
I also try to bounce mine - you know they’re ripe if the bounce at least half the distance back up. They never seem to be ripe though . . . .