I'm not sure there is a math concept that is more hands-on than measurement. Ok, my measurement activities depend more on feet than hands but you get the idea. Measurement is all about active learning. The first thing I do is send home a note asking for everyone to trace their own foot and the feet of three other people of varying sizes. This gives us plenty of feet for measurement practice. Since the first grade CCSS is for measuring with non-standard units, we use paper clips and Unifix cubes.
However, I think first grade students are capable of measuring with rulers too, so I also include some standard measurement in this unit.
Then it gets even more fun. We measure ourselves with cubes and look for things that are longer, shorter and the same height. Talk about a lot of measuring practice! They are measuring everything.
When it comes time to count how many cubes long the classroom is, there was some debate about the easiest way to do it. Finally they came to the conclusion that bundling into tens makes sense. I walked away before they bundled into hundreds, at least I hope they thought to bundle into hundreds.
There's a lot of buzz with this unit, but nothing is better for creating an understanding of a concept than active learning. I would love to give away my Hands-On Measurement Activities for first grade to the first 3 comments. Make sure to leave me an email address or email me at: firstname.lastname@example.org. It's also available at my TpT or TN stores.