This one doesn't come from some college class, or great pin off of Pinterest. This idea was born as I was wandering through the store and noticed these ketchup/mustard bottles on sale for less than a dollar. I've actually been wanting some of these for a couple of other activities, but when I saw them in the store that day I knew right away what their primary use (at least for now) would be.
If you want something simple to prepare and engaging for your toddler, this should do the trick. All I do is fill up both bottles with water and turn Erik loose outside. He gets to enjoy spraying water all over while also building those hand muscles.
Once the bottles is more empty than full, it gets harder to aim and squirt at the same time, so I trade him for a new bottle. When the next one is getting low I combine the two together and he's ready to go for a few more minutes without my having to go back inside to refill bottles at the sink.Erik would keep spraying things for as long as I'm willing to keep refilling his bottles. This particular day he started trying to spray each individual pebble in front of our apartment. If he'd had an unlimited supply of water (aka a less lazy mom) he could've been occupied for a VERY long time.
Building a child's hand muscles is very important since they will need strong hands/fingers to be able to write some day. The more fun you can make this muscle building the more effective it will be.