Shouldn't ninety six be written all as one word, thus nouăzecișișase? If not this contradicts the number guide written below the lessons.
I am not aware of the guide, but nouăzeci needs to be written as one word instead of nouă zeci (and so should douăzeci, treizeci, ..., optzeci). But the rest is alright as it is.
Google yields both versions, douăzecișitrei (like in the Duolingo notes) and "două zeci și trei" (Google with quotation marks!)
"Read" can also be past tense, reported.