My hope is to keep this site running for free with the majority of all its content remaining free. But, as you can see, the materials used for the projects do cost money. All materials are paid out of pocket (I do not get to expense them nor do i get to use them as much in my classroom since i began teaching college full time).
Here are some things you can do
Send us a donation via the paypal button on the home page
Send us some supplies (contact firstname.lastname@example.org for our address)