The historical subject that is conveyed in the exhibit and how it is conveyed (use of artifacts, media, labels, commentary, etc., or some combination thereof). These first two points should be made very briefly, as a simple matter of fact. Points a. and b. should be no longer than one page, combined.
Purpose(s) of the exhibit.
What argument does it make about the past? Intended audience?
Who is expected to be persuaded by the argument the collection makes?
Presentation of evidence. Tell in some detail what was in the exhibit or site that convinced you of its purpose.
Does it reflect sound historical scholarship?
Does it employ an appropriate use and mix of artifacts, images, narrative, and/or other source material?
How effective is the exhibit design?
How well does it achieve its purpose(s)?
Did it leave anything out, and if so, were those omissions deliberate, accidental, or due to lack of material or artifacts?