Hello,
1. I was too timid (adjective phrase) to approach any of the white people. (noun phrase) YES
2. It would be the first school (noun phrase) for negro children (prepositional phrase) that had ever opened (verb phrase)on that part of Virginia. YES
Here I have some doubts.Shall I write "the first school for negro children" as noun phrase or as I have already shown above.
The first school for negro chidren -- what?
If you can substitute a group of words with one word, then it is a phrase. As you see above, "The first school for negro chidren" is a phrase, and it comprises many more sub-phrases: negro children, for negro children, school, first school, the first school, school for negro children, etc.
3. It was to be a great and wildly exciting event. (noun phrase) Yes
4. I was bitterly disappointed. (adjective phrase) Yes