One area we frequently struggle with is time. When my students and I are engaged in an activity, we sometimes lose track of time and miss some of our objectives for a day. Sometimes this is ok because the engagement trumps the schedule, but there are times when we need to get something done.
I've used a variety of online timers and the Omnibox in Chrome to set timers. This has worked, but it always involves an extra step.
Recently I discovered a more efficient way to time activities in my classroom. I discovered that YouTube has a timer for just about any time frame I am looking for. I've started to embed a YouTube timer on the objective or instruction page that I am projecting.
Here is an example with instructions if you want to learn more.