Add a personalised map to help participants find your event's location, show parents where the field trip is or have students create interactive maps relating to their studies.
Create using mymaps and then insert using the Map option under Embeds.
You can add a video from YouTube or directly from your drive. Just select YouTube from the insert menu. Then "Video Search" or "Uploaded"
This one will show you how to use Drawings to create a button for your webpage.
You can add a photo gallery by using the "From Drive" option from the Insert Menu and adding a folder of pictures to your site. After adding the folder, click on the settings icon and choose grid view to make the photos viewable.