Here's a fantastic Easter idea I just found online. I've seen similar ideas, but this one is the most simple (and lowest in cost). Even though Easter is upon us already, it is still a really fun idea to do over Spring Break.
a small terracotta flower pot
a large terracotta saucer
shade grass seed
twigs & string (to make crosses)
one large stone
Following example in the picture, fill part of the terracotta saucer with potting soil. Place the small clay pot (the "tomb") on the dirt and pour more soil over top. Gently pack it down. Fill the area in front of the small pot with small rocks. Place the large rock in front and off to the side of the small pot.
Create three crosses from the twigs and string. Gently press into soil.
Sprinkle grass seed generously on top of dirt, moisten with a spray bottle. Keep the seed moistened by spritzing several times a day with spray bottle. Set it in a warm sunny location.
Grass should in 7-10 days.
Notes: You can use a plastic saucer and small pot. If you use regular terracotta, I recommend you place something water-safer under the saucer. Mold can build up under terracotta pots due to the moisture they retain, damaging the surface beneath the pot.
If you don't have nice little stones you can use, they are sold in home decorating departments at stores (often with the vases).