This 176-Piece STEM Toy Kit from DynaMax via Amazon.com drops from $34.99 to $14.49 when you clip the coupon on the product page. This sells elsewhere for $30. Shipping is free when you use a Prime account or free Prime trial. It's also free on orders of $35 or more. Otherwise add $6.99. The BPA-free plastic pieces can be used to create up to 42 designs. It has a 4.7 out of 5 star rating based on more than 6,500 ratings.