simple hydraulic claw
This is a simple syringe based hydraulic claw I sketched up for my kids. It also requires a couple of syringes (5ml & 3ml), 8" of small tubing ( I'm not sure of the size but it needs to fit tightly over the end of the syringe tip), 2 or 3 small zip ties to attach the syringes. It also requires 12 M2x10 screws and nuts.