In Seed Ecology/Seed Science you sometimes need to cut a seed in half — in my case, it was so that we could get it under a microscope or x-ray machine so that we could measure the thickness of its protective seed coat. Cutting seeds in half is also a great way to show students the different parts of a seed, especially if the seeds are stained to improve contrast.

(I suggest a lesson plan based around this seed cutter below, where students compare the germination time of seeds with damaged or intact seed coats.)

Above: A diagram of a wheat seed. (Source)

Cutting seeds in half usually involves holding the seed with pliers while you cut it, but you may crush the seed or lose it. Moreover, very small seeds (1 mm wide) are difficult or impossible to hold with pliers.

This seed cutter makes the process fast and easy.

1. Place a seed into the bowl and tap the cutter on the table. The bowl's elongated shape will cause the seed to align lengthwise.
2. Place a standard scraper blade into the slot. Hold it in the center so that your fingers cover the bowl and prevent the cut seed from flying out.
3. Push the blade down. The seed will be cut near its center line.
4. Invert and tap the cutter on the table to free the seed.

The slot passes through one side of the cutter so that you can push out any debris that settles inside it. The cut seed in the photo gallery is a chive seed measuring 3 x 1 mm (0.118 x 0.039 inch). Even a seed this small was aligned and cut in the correct direction!