There are several ways you can use Padlet in the classroom. One way would be to post a question about your lesson on the top of the board and have the students post their responses to the board. This way, the students can see other students responses and learn from what the other students wrote. Some may say that is bad because students will just copy someone elses response. That will be up to the teacher to set the norms before they begin the activity and make sure the students know that they must post a different response than other people.
Another way to use Padlet, would be to create a webquest for your students. You could take a topic that you will be working on and create a lesson for the students to complete online. You can put a picture in the background that deals with the topic and then add several different pictures or videos onto the board. Each video or picture can give the students more information about the topic. You can link the pictures to specific websites that will give them more information about the topic. After the students have completed all of the reading and watching videos, you can have them answer some questions. You can do this several different ways, but one that I suggest is a Google form. You can create a Google form and then put a link to it on the Padlet wall. If you have not used Google forms, read my blog about The Amazing Flubaroo.
There is a lot that you can do with Padlet to keep your students involved and interacting with your lesson. Like with anything else, just take a little time to explore it and see what works best for your classroom!