Google Keep is a tool I use every day. Think digital sticky notes… But Google style, so they are collaborative and work with Docs and Slides.
Hashtags are Labels
Using hashtags in a Google Keep note helps you to search for things you want to get back to. Using a hashtag in a Keep note automatically labels it in a folder for you.
Notice on my screenshot from my phone that I was saving a recipe (https://www.southernkitchen.com/articles/eat/16-thanksgiving-appetizers) and I tag all my recipes I want to get back to with #recipe. Notice the note automatically added the label for me.
As you find lesson plans or ideas you want to save, work out a hashtag system for yourself when you save the information to Google Keep.