Learning Resources Twisty Droppers. These fun educational tools are great for developing hand strength and fine motor skills in young learners! The pipette styled droppers are great fun for use during water play and bath time and can be used for a variety of science exploration activities. Each dropper measures 15cm long and features a soft, durable bulb, ideally sized for little hands to squeeze. Set includes four Twisty Droppers in a useful storage tub. Suitable for ages 2+.