"...these articles should be of value to students..."

Can anyone tell me what does "of" mean in this sentence?
I've never seen "of" used after "be, is, are" before... I'm only familiar with the phrase "something of something".

"be of value" can be read as "be valuable"

How can I be of use to you? How can I be useful to you?
can be of value
would be of value
should be of value
might be of value

are all very frequent
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Hi Grammar Geek and Marius Hancu, Thanks a lot Emotion: smile
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A form of "to be" followed by "of" and a noun is usually equivalent to "to be" followed by an adjective of similar meaning. It is an idiomatic use of an "of" phrase. Here are some other examples.

to be of use = to be useful
to be of help = to be helpful
to be of importance = to be important
to be of significance = to be significant
to be of consequence = to be consequential
to be of interest = to be interesting
to be of assistance = to be helpful (because there is no word "assistanceful")
to be of worth = to be valuable (because there is no word "worthful")
to be of good quality = to be good with respect to quality (because there is no word "good-quality-ful")