This is an idea for those teachers in schools who do not have budgets for area rugs in the classroom. Lowes and Home Depot have carpet remnants sections where you can catch a good deal on area rugs for the home or classroom. The are left over pieces of carpet that they bound on the ends.
Pictured above is a 6 x 8 rug that I purchased for my living room for $42. A teacher friend of mine showed me how to tape the "no slip" rug underlay to the carpet with wide masking tape so it would move with the carpet and not show if the carpet was moved. I was at the store and I looked at the "no slip" underlay and it cost over $40 (more then the carpet I was buying!). I simply reused the one I had under the old carpet...it was a bit small but it should work (underlays would probably be cheaper at Walmart...or you could use the foam shelf liners and just do the perimeter and not the area).
They don't have cute rugs with maps and states but they are inexpensive and can be used as a reading area or working area for children.
My advice is to not purchase it in any "off white" color. I had to replace the rug I used to have in my living room because the foot, pet, and child traffic had discolored and stained it beyond a simple steam cleaning.