Building toys provide hours of fun that can carry on for days at a time. They’re also a sneaky way to fit in some brain work into playtime. Czech-based Walachia creates wooden hobby kits for kids (or adults) to construct their dream building using a Jenga-like design. Like next-generation Lincoln Logs, the kits make use of complex designs and real wood blocks of different lengths. With many kits to choose from, including castles, windmills and classic log homes, the challenge can span 100-600 logs.