Do your students need some practice measuring volume? Here are some simple ideas to get them up and actively measuring and calculating.
Label each block with a letter (use masking tape if you don't want to mark on the block itself). Calculate the volume of each and create a key.
Collect empty boxes of a variety of shapes and sizes. Label each box with a letter. Calculate the volume of each and create a key.
Again, label each jar with a letter. Determine the volume of each and create a key.
Save your blocks, boxes and jars and next year you'll be ready to go, with the key and everything. Just pull it out and have your students get to work!