Use the letters of any word, in proper order, placing them vertically. Then write a verse, each line starting with the letter that starts the line: Fun for children’s poetry-writing exercises, where they use their own names or any word word(s) they choose, such as MY NAME. Here's an adult effort, proving it is not as easy to do as it may appear. Grownups and children play acrostic games.
More than I can tell you right now
Your permission for me to sing makes me Wow!, for
Nothing is as thrilling
As hearing a fun song spilling
Melodiously from iPOD/CD
Especially if with you sing it with me.
Other places where acrostics are found? In languages all over the world. For example, the psalms in Hebrew, using the entire Hebrew alphabet-27 letters.