As far as DIY advent calendars go, this one is pretty simple to make. While you can also purchase the printable template online, this is also a craft you can easily replicate at home.
Like other DIY advent calendars, you can fill up the small squares with whatever treats you would like. This comes in especially handy for children with food allergies or for giving small gifts instead of chocolate. The simplistic design consists of 24 small paper cubes you print out and construct yourself. Each one is separate, so you can arrange them to create a Christmas tree or any other seasonally appropriate shape. If you choose to create your own, you can also customize the font or use different colored paper. Kids can also decorate their own.