I think these T-Shirt Graffiti pens that are only $5 (reg. $9.95) from Chapters.Indigo.ca would be fun for a birthday party! Here are some details:
Great quality fabric marker pens with loud neon UV inks! Perfect for cotton shirts, caps, canvas trainers and more. 8 high quality permanent fabric markers in bright washable colours. Colours can be air-cured for 24 hours or fixed instantly by ironing. Once fixed colours are permanent and can then be machine washed or dry cleaned.
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