Today I looked in the nucs - just to see what's going on. This is Nuc #1 - they're working hard - no queen, it's to early. They have taken almost all their sugar syrup.
I did change out two of the frames in Nuc #2 - the outside ones - put in two that I had from last year. They were only working on the three inside frames - I had originally put in two new frames which in hindsight wasn't such a good idea.
All important ventilation - drilled two holes in the inner cover and the stick to give even more ventilation when the top is put on. Do not have screened bottom boards on the nucs - sure wish they did.