Many preschoolers will enter preschool already recognizing and being able to name a few shapes and colors. Since it is a topic that most small children love, it's a topic they can be very enthusiastic about. Take the learning experience slow, concentrating on a few key shapes and colors at a time. Mix the study of shapes and colors to keep the kids interested. Have the children look for shapes and colors in their daily environment. Ask questions like "what shape is this ball" or "what color is the sky" to tie the study in with their world.
Letter and number recognition is a key topic for preschoolers. As the foundation for learning to read and learning mathematics, being able to recognize the numbers 1 through 10 and being able to count in order is essential. Being able to pronounce the name of each letter and recognizing it when they see it can be taught through a variety of crafts, games, songs and hands-on activities. Start with a single letter and number at a time, thoroughly studying it before moving on to the next one.
While most preschoolers aren't consciously interested in healthy habits or nutrition, it is a great time to start educating them about the importance of health and nutrition. Start by making all cleanup activities a class project, discussing when they need to wash their hands and how. Discuss what foods are healthy foods or not healthy foods, and why. During snack time each day, discuss the healthy elements of the snack and the hygienic way to prepare and clean up at snack-time.
Frequently, preschoolers know their birthdates and understand the basics of major holidays, like Christmas and Halloween. Because kids love parties and celebrations, they are eager to learn about the variety of holidays that occur each year. However, teaching the days of the week and the months of the year is also great way to get them started on understanding where those holidays occur on a regular basis. Incorporating a daily study of what day, month and year it is will get them started on understanding the basic cycle of the planetary year.