s=NDSolve[{D[u[x,t],t]==D[u[x,t],{x,2}],
    u[x,0]==Sin[5*Pi*x],u[0,t]==0, u[1,t]==0},u,{x,0,1},{t,0,.01}];
Plot3D[Evaluate[u[x,t]/. s[[1]]],{t,0,.01},{x,0,1}]
