Sand Dollars
A lesson Planned by Jenny Ziehler
What we will cover
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Legend of the Sand Dollar
What really is a Sand Dollar
What they look like
How they eat
What their life cycle is like
And different types of sand dollars
Story Of the Sand Dollar
 In Maine, children where taught to
believe that sand dollars where
pressed sand
 Another legend claims that Sand
Dollars are money for mermaids
 Another Legend Claims, There are
five doves inside, If you break a
sand dollar open, the doves will be
released, bring peace to the lands.
What is a Sand Dollar
 A marine invertebrate closely related to the sea
urchin
 The doves inside the sand dollar where actually once
the teeth
 They live on the bottom of the sand sea floor, hiding
under sand when threatened.
What does a Sand Dollar look like?
 A live Sand Dollar is described as
looking like a fuzzy cookie.
 There is cilia on the bottom of the
sand dollar for transportation and
helping them feed.
 They have a 5 part radial
symmetry
 Skin is made up of hard calcium
carbonate plates
 Grow up to 4-5 inches
How do Sand Dollars eat
 Sand Dollars pick up minute
sized organic particles from
the ocean floor
 The hole in the center of the
bottom of the sand dollar is
where the mouth is located
Life Cycle
 Sand Dollars will often live in
large groups
 Most often living to 6-10 years,
they reach sexual maturity
between the ages of 1 and 4
 Sand dollars are external
fertilizers
Different types of Sand Dollars
Arrowhead
 Flat with indents along
the outer edge
 Found mostly along
the western coast
Sea biscuit
 Small round and
puffy
 Has five large petals
 Flat on the bottom
 Sometimes found in
florida
Interesting facts
 Sand dollars in colder temperatures
have no holes
 Sand dollars in tropical weather do
have holes in them
 Sand dollars found on the beach are
most often the empty shell of the
dead sand dollar
 They will burry themselves standing
strait up to avoid getting washed
away with the tide