To send video or photo messages to the Educator simply do the following:

Step 1 - Log into your account. If you don't know how to log into your account see this article

Step 2 -  Choose the option "Create message".

Step 3 -  Select the child(ren) the message is about

Step 4 -  Write the message

[OPTIONAL] Step 5 -   Go to the Camera icon and choose a photo/video from your Image Gallery and voilà!

This way you will be able to send a message to which only the Educator and the Manager have access :)

If you want to send a message that only the Management has access to, see this article