Many of the hashtags have “meeting times” where educators agree to “meet and tweet”–that is, send out messages on a topic at a certain time on a certain day.
If you do participate at the agreed upon time, you’ll see the tweets stream in live and participate in said conversation (via twitter) in what is nearly real-time. But if you can’t make it, the great part about a hashtag is that it does the sorting for you. You can search for messages assigned to a given hashtag anytime–tomorrow, Sunday night, or during your planning period next week.
Great list of Twitter Hashtags
