Warren Township High School and River Trail School were affected, with some children being bused to Viking Middle School until the situation was resolved.
It started before the school day began, but police say the situation ended shortly before 11 a.m.
Police say a man fired a gun inside a home and then holed himself up inside the house.
Police say the situation appears to be domestic and the man who fired the gun is under arrest.
The schools that were on lockdown are back to normal operations now.