These are email address requests from Sports Illustrated for kids. If you give them your email address they might want to sell it to another web site then that web site would try to sell something to you.

They might want to send you junk mail by getting your email address or spam. Spam is something that lets people send junk mail to your email account. They can also give you a virus that messes up your computer. They can use humor to try and make you laugh and they are trying to persuade you to buy there items.

Sites will also offer free postcards that you can send to your friends. When you do that, you are also giving the websites your friend's email address. So you might be sending spam to your friends when you're just trying to send them a nice note. Which ends up not being so nice after all.