JUnit not compiling

I have been making projects with unit tests all year. I just made a new one the same was as before and am getting this error:

   error: package org.junit does not exist
   import static org.junit.Assert.*;

My header looks for my file looks the same as the header that is generated by the Unit Test tab.
import static org.junit.Assert.*;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

Can anybody tell me how to fix this compile error? It seems like the paths are not setup the same as they were before. Something changed and I do not know what.

Thanks for any help!