9/22/23 - MrNussbaum.com is NOW 20 Years old. Celebrate our birthday with a 60% off present when you register for MrN 365- the subscription, ad-free, all-content, teacher-curated, enhanced feature version of MrNussbaum.com. Use the code happybday
In Sand Dollar Exchange, you play the role of a brave little ocean crab who must pick up the sand dollars and fractions of sand dollars and drop them on their correct clam shells. Time is of the essence! If you finish the game, the Sand Dollar Exchange awards you a certificate. If you finish the game within 200 seconds, you can earn a sting ray certificate, within 300 seconds, a horseshoe crab certificate, and within 600 seconds, a hermit crab certificate.