The students are on a summer bus tour dedicated to registering young people to vote and promoting gun law reform.
The tour reportedly includes more than 50 planned stops in over 20 states including Wisconsin and Illinois.
More than 500 people came out to the Wisconsin Center tonight to hear their message.
The bus hauling the Parkland students across the country has a revolving door.
Students from different cities are jumping on and off at different stops along the way.
"This can't keep continuing, like our future is literally being killed right now," said Tatiana Washington, a student at Rufus King High School. "We need gun reform now. We need our communities to be safer."
On February 14, a shooter killed 17 people at Marjory Stoneman Douglas High School.