I like the Kallax shelves, also. They are great to use as book shelves, but they are also great in conjunction with the drawers, so you can ‘hide’ all the little materials like manipulatives and flash cards. I also just bought the green, pink, and black cardboard organizers at IKEA. They work great for work books and supplies.
Also, we were there this past weekend. They had a promotion going on that if you eat in their restaurant and spend at least $100, they will deduct your restaurant reciept from your bill: FREE MEAL! Yay!