Hi,

You can do the following:
1- Select the entire spreadsheet first and right click to go to Format
Cells.
2- Go to the tab called Protection. Excel by default uses protect for
all the cells.
3- Uncheck the protect option there.
4- Now select the cells that you want to be protected and on those
cells right click to go Format Cells option again.
5- Check Protect option for those cells and if you do not want your
boss to see the formulae in those cells then you can also check
hidden. By checking hidden, he can see the result of the formulae used
but not the formulae itself.
6- Lastly, after you have protected all the desired cells you still
need to protect the spreadsheet using a password. But when you protect
the spreadsheet you are only protecting the cells for which you had
chosen the protect option on. All the other cells will still remain
editable.

Hope that helps.

- AG