Every four years something funny happens with our calendars -- we add a day! Why do we do this? Discover the science behind leap year.

Is a feather liquid, soft, spotted, or heavy? Practice describing everyday objects, or matter, with this second-grade science worksheet!

What do a key, a goldfish, and a tortoise shell have in common? Find out with this second-grade science worksheet!

Practice describing different objects and substances in this colorful worksheet!