Your understanding of the meanings conveyed by the words is sound, but it's your understanding. In the way they are generally used, there is considerable overlap in the 'meaning' conveyed by them When my trainee teachers wrote lesson plans, they knew exactly how to word their aims and objectives, and would be corrected if they use these words inappropriately. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.