BE@RBRICK is a toy produced by MediCom Toy Inc. in Japan. They are collectables that come in a variety of materials, colors, decorations, and themes, from "horror" to "cute" to "animal" to "scifi". All BE@RBRICK figures have the same basic shape (that of a cartoon bear). Like trading cards, they are typically sold in packages that do not indicate which BE@RBRICK is inside and have predetermined ratios of how many are produced (thus making some rarer than others).
BE@RBRICK created two figures for noodles: one for the album long long chain, which has "Ain't nothing like the noodles" written on it (comes in cream pink or yellow), and one for the single Lesson 1, which features the BE@RBRICK wearing a Lesson 1 t-shirt. The Lesson 1 BE@RBRICK was included with the limited edition Lesson 1 single.
The other track on the Lesson 1 single, Left hand daughter, is listed as "theme of BE@RBRICK"; it's an absolutely adorable song Yoko wrote in honor of BE@RBRICK's anniversary. Thank you to terra for helping me translate this information that came with the Lesson 1 single.