Complete a chore with a robot arm

What can we use instead of wooden skewers, popsicle sticks, or a clothespin if we can't find them?

Use a bamboo chopstick or a sturdy straw pushed through the cardboard for the shoulder/elbow pivots, replace popsicle sticks with cut cardboard strips or craft sticks taped end-to-end for the arm segments, and swap the clothespin gripper for a small binder clip attached with tape as in the 'Attach the clothespin' step.

My arm won't rotate smoothly or the gripper won't close properly—what should I try?

If the shoulder or elbow sticks, widen the cardboard holes a little or add a tiny spacer (a scrap of tape or bead) around the skewer and then follow 'Gently pull each pencil to test' to adjust string lengths and tape until the arm lift and gripper move smoothly.

How can I adapt this robot arm activity for younger or older kids?

For preschoolers, have an adult pre-cut the 20 cm cardboard base and pre-thread the skewers while the child tapes the popsicle sticks and practices pulling the pencil controls, and for older kids, challenge them to lengthen the segments, add a third joint, or replace a pencil control with a simple pulley mechanism.

What are some easy ways to extend or personalize the finished robot arm?

Decorate and label the 20×20 cm base, reinforce the clothespin gripper with a rubber band for stronger holds, add color-coded strings or a third pencil control for more complex pick-and-place tasks, and then share a photo or video on DIY.org as the final outcome.