Is it therapy dough or moldable kinetic sand? Mad Mattr is both. Sculpt, stretch… Is it therapy dough or moldable kinetic sand? Mad Mattr is both. Sculpt, stretch—even crumble—it and watch the texture change from sandy to silky soft in seconds. Projects For Kids, Diy For Kids, Crafts For Kids, Craft Projects, Fun Crafts, Diy And Crafts, Arts And Crafts, Sensory Activities, Toddler Activities