1. Let's wrap up this lesson.

2. Let's finish this lesson.
3. Let's summarize this lesson.
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What does #1 mean? Does #1 mean #2 or #3?

1 means 2.

3 is related, but not exactly the same.

In this context, when someone says "Let's wrap up this lesson," it means they are suggesting that the lesson should be concluded or finished. So, #1 means the same as #2 - "Let's finish this lesson." "Wrap up" is a common informal expression that means to bring something to a close or to complete it. It implies that you are reaching the end or conclusion of a particular activity or event. The phrase "Let's summarize this lesson" in #3 suggests a slightly different meaning, as it specifically refers to summarizing the main points or key takeaways from the lesson, rather than simply finishing it.