A Free Online 3D design Program Grade 3-12 Tinkercad is a free, easy-to-use app for 3D design. It’s used by teachers, kids, hobbyists, and designers to imagine, design, and make anything! Tinkercad could be used in numerous ways. Teachers check out this list of lesson arranged by grade and subject. Create, save file and print using 1 of 5 SRPSD’s 3D Printers.