A couple of tools that can help you to remind, or to plan activities in your teaching life:
An example of planning list with reminds:
That releases mi mind for remembering some ideas.
Evernote, is another example for more than gathering simple notes:
That was one remind of a link for my lessons planned for an special date.
You can use any app or directly you can shoot digital reminders directly with pictures at your device, ready to use at class, stored in dropbox or your own pendrive.
This example was taken for teaching energy, and the three phases for obtaining the electricity comsumption.