My Take
If you are looking to implement project based learning within your classroom, Mathalicious is a great place to start. The lessons are truly engaging and the students love working on the projects rather than the old "sit and get" method. One of the drawbacks is that you have to pay $10-$30 a month for the website. I do believe that the lessons are worth the money, but as a teacher I know that it can be a struggle to pay that much for one website.
How I Use It
Mathalicious is a great website to obtain fully developed lesson that involve real world issues and problem solving. My classroom has transitioned to a PBL (Project Based Learning) classroom and this website allowed me to have instant projects that correlate directly to the common core. Lesson were designed to engage the students and deal with issues that spark student interested, such as, music and sports. My students and I specifically enjoyed the Big Foot Conspiracy lesson. This lesson started with the question, "Should people with small feet pay less for shoes?" You could tell by the looks in the room that students had never thought about it and it sparked instant engagement! The lesson gives you specific task that the students will be carrying out and how it aligns to the common core. I appreciated how it used real world companies such as Zappos and Nike to engage students. All resources to carry out the lesson were there to download which made my life much easier!