Hagoromo chalk has developed a cult following among mathematicians. ... ‘The first stick is free,’ chalk dealer on the block in my department,” says Max Lieblich, ...

And Chelsea Ritter-Soronen, owner of Chalk Riot, a women-led street art crew, said Chalk Walk was her dream collaboration. Dallas Carter, 4, enjoys the day out. Dee Dwyer for NPR hide caption ...

The Chalktrail is an add-on which turns any bike or scooter into an artistic tool by holding a stick of chalk which is pressed to the ground behind you as you ride, ...