Prime Day can be overwhelming, especially when trying to find more affordable items to fill your shopping cart with. These are the best Prime Day deals under $100, from smartwatches to LifeStraws. Prime Day ends tonight, so this might be your last chance to score a great deal before Labor Day or Black Friday. Be sure to check out our full list of the Best Prime Day Deals and find highlights in our Prime Day liveblog. Photograph: Amazon Valtech Magna-Tiles $50 Amazon Magna-Tiles—beloved STEM toys—let kids build 2D/3D creations with magnetic shapes.