When you think of graphing, you probably think back to stale worksheets in your third grade class, or to more complicated parabolas in high school calculus. Graphing starts out as a very simple concept, one that can and should be explored with preschool children, particularly the four year-olds. One of my favorite ways to do that is with a Post-it graph.
The easiest way to start with the concept of graphing is to chart the number of boys vs number of girls in a group. It is a clear-cut dichotomy (in preschool anyway :)) . Start by having the children look around. Do they think there are more boys or more girls? In a larger group, this is often harder to do just by looking. We need to organize the information to make it easier to compare. Show your prepared chart, with a grid divided between boys and girls. Explain to the children that you will be using this grid to graph how many boys and how many girls are in your class. Ask each of the girls, one by one, to come up, get a Post-it and place it on the chart above the “Girls” label. Remind them that each person only gets one sticker, and that when we build a graph, we climb up the chart like a ladder: one sticker per square. Next, invite the boys to do the same thing.
Here’s a simple game that children love to play! With a group of children in a large area, have one child stand, at least 10-20 feet back, facing the other children as they stand against a wall, fence, or other object that can serve as the “safe zone”. The children standing against the wall chant, “Dinosaur, dinosaur, what time is it?” The “dinosaur” replies with any “o’clock” time. The time serves as the number of steps forward the children take. So, if the “dinosaur” says, “5 o’clock”, the children take 5 steps forward. The children continue in this pattern until the “dinosaur” says, “Lunchtime!” At that point, the children run back to the safe zone with the “dinosaur” chasing after them. If the “dinosaur” touches one of the children, that child becomes the next “dinosaur”. (Reinforce to the children, that they only need to touch the child they catch, not push or tackle.)
Here’s a color-mixing project that is quick, easy, and inexpensive. Fill three clear containers(jars are great) about 2/3 full with water colored blue, yellow, and red with liquid or powder water colors, or with plain old food coloring. Provide a few extra empty containers for mixing. Place all of these on a towel-lined tray, or in a sensory table. Provide a baster or dropper for transferring water, or provide several different instruments of varying sizes for experimenting. Children will be absorbed in this activity, transferring water and creating new colors, while building a bundle of developmental skills! 
Here’s a great fingerplay for a snowy day:
