Growing celery from the base of the stalks is a fun project that couldn't be easier—plus, it's great to do with kids. The celery sprouts surprisingly fast and, except for the cutting part, even very young children can do the whole project. If you are looking for activities to teach science and math skills, have the kids measure how fast the celery grows. There are two ways to do the project: using just water or in a container with potting soil. If you are just sprouting in water, this project can be a good one for winter when it's particularly fun to see something green and growing indoors.