Auditioning for St Martins

Hi everyone, I'm just after some advice. I'm auditioning for St Martins Youth theater in March and I need to prepare two contrasting monologues and a 'special skill' presentation lasting one minute. The monologues I can probably work out on my own but I'm really stuck on the special skill. Their site says you can sing, do a dance, juggle crayons etc., so anything creative really. Only I'm a terrible dancer, I can't sing and I've never juggled. Can anyone recommend anything? I'm open to all suggestions. Perhaps someone's been to a St Martins audition? I'd really appreciate some help! Thanks in advance! Natasha