Can I take deductions for room in my house used 5 days per week mainly for contract educational work, but room also contains household supplies?

It depends on what you actually use the space for.  You must use it regularly and exclusively for work.  You can have de minimis personal use (minimal, insignificant).  For example, if you have converted a second bedroom for work, but you need the closet to store other household supplies, and you occasionally go into the room to get stuff out of the closet only, that would generally be considered de minimis.  However, if your converted workspace has a TV that you watch when someone else is using the main TV for something else. that would not be de minimis, that would be using the space for personal living space.