That is good! 
Also, don't forget that the students could use good old fashioned PowerPoint to create a presentation as well. I wonder if you could incorporate that into Voicethread so that others could make comments?
Going Paperless - Activity #1
Geometry - Triangle Properties
Background Colour
Font Face
Font Kerning
Font Size
1
Image Visibility
Letter Spacing
0
Line Height
1.2
Link Highlight
Text Colour