is this the correct punctuation My friend jumped off the diving board and shouted "look out below!"
No.
http://www.grammaring.com/punctuation-in-direct-speech
Try again!
Yes, the punctuation in the sentence you provided is correct. The sentence is punctuated properly with a period at the end, as well as quotation marks around the direct speech ("look out below!").
To punctuate this sentence correctly, follow these steps:
1. Start the sentence with a capital letter because it's the beginning of a new sentence.
2. Use a comma before the conjunction "and" to separate the two independent clauses ("My friend jumped off the diving board" and "shouted 'look out below!'").
3. Enclose the direct speech, "look out below!," within quotation marks. Use double quotation marks in this case.
4. End the sentence with a period because it is the end of a complete thought.
So, following these steps, the correctly punctuated sentence is: "My friend jumped off the diving board and shouted, 'look out below!'."