These are the supplies I order over and over again and are essential for teaching elementary art. I am sure other supplies are great, but these are my favorites.
Crayola Tempera Paint in a variety of colors. The white and yellow paint in other brands is very translucent but I like the texture and opacity of this brand for nice coverage. I use this for my cherry blossom painting and for sponge painting.
Sax #10 round paint brushes. These have a nice spring to them and they are a good size for young children. I have been very happy with the quality at the price. I purchase these brushes from
Saxart.com
Super large round brushes with a nice tip for watercolor washes and large scale painting. Sometimes these are called stubby brushes. I tend to spend more money on this item to get quality rather than buying these in bulk as the cheaper brushes have flyaway bristles. A nice set of these will last a long time.
Cray-Pas Oil Pastels. These come in a variety of sizes, but I usually order the 25 color sets. This gives a nice variety to the color and allows for shading. If you get the larger color packs, the primary colors will be used up before all the rest of the colors. In teaching 200 children with a project, 25 boxes will b used up by the end of the project, so you will need to order enough boxes for multiple projects depending on what you will doing.
Sharpies -- both fine point and regular point. I love love love these for outlining. If you are teaching 200 plus children, you will need multiple boxes as the points will start to break down. I usually buy 6-8 dozen of each size per year depending on the projects I am working on.
Basic Watercolor Sets - Get a good brand for the best color. More expensive paints have less filler and more color. My basic advice is that you get what you pay for. 30 sets will last a long time especially if you refill the colors you use up.
Crayola Construction Paper Crayons - Bulk Pack. We don't do many art projects with crayons, but when we do, this is the crayon I use. I try to buy a bulk pack box of these each year and they are my favorite for anything we do on construction paper.
Watercolor Paper - I have struggled finding a good student grade watercolor paper in past years. Right now, I don't have anything to recommend to you. I have found that the quality of paper is going down and that sometimes the paper won't work with a certain process. I would recommend that you buy the best paper you can afford and test the paper before you begin the project. For student work, I am leaning toward the Canson Student Grade Watercolor pads that I purchased from Art Supply Warehouse. Heavy weight 80# drawing paper can also work well for painting with young children. For my own work, I use Arches 100% cotton 140 pound paper. I prefer the cold press because of the texture, but the hot press has a very flat texture and is also very nice.