The following information comes from Serebii.net:
Serebii Note: Pikachu to be able to be made at Build-A-Bear from Early 2016 in US, Europe, Canada and Australia https://t.co/oV6DIIA7Ub— Serebii.net (@SerebiiNet) October 20, 2015
The Pokémon Company International and Build-A-Bear Workshop have revealed that from early 2016 you'll be able to make a Pikachu at Build-A-Bear stores across the US, Europe, Canada and Australia. If you do this, you'll get a special promo TCG card as a gift and you can decorate it with a Poké Ball Hoodie and have a Pikachu sound chip. If you order it online, you'll also be able to get a Charizard costume.