We’ve got a new Canvas plugin and tutorial coming out tomorrow that we show you step by step how to make a really lovely one pager with Canvas :)
Child themes are not normally for children :) They are to quote from the wordpress codex
“A child theme is the safest and easiest way to modify an existing theme, whether you want to make a few tiny changes or extensive changes. Instead of modifying the theme files directly, you can create a child theme and override within.”
So you only need one if you want to modify css or php files within your theme.