The Aquafarm costs about $60, depending on what promotions they have running at the time. For that price, I think it's a definite buy if you have any interest in gardening or aquaponics. It's also a great gift for a garden lover.
However, students who attend lower-ranked schools can still take a rigorous curriculum. Wherever you go to school, it's important to take the most advanced courses available and to take advantage of elective credits to strengthen your engineering education.
Why is critical thinking Important? Along with a measure of Intelligence and memory, your students need critical thinking skills in order to be successful in the world beyond high school. Your students need to pass exams and as a teacher you must prepare them, but you will only be able to give them a true education if you foster critical thinking skills within them.