Ever have a kid who wanted to tip the cup instead of use the straw? Or where the straw was so long that it was above the kids head with the cup on the table?
Bend the straw to a 90 degree angle. Then use your fingernail to put a crease in the fold, and squeeze together. The straw should retain the 90 degree bend, and slow the drink rate a little.
Thanks for the hack, Sarah!