My grandkids had a great time collecting pressed, or "smooshed" as they called them, pennies last summer.
I saved quarters and pennies for months in advanced, then put 20 quarters and 10 pennies each in a bunch of snack size ziplock baggies.
We bought penny press collection holder thingies at the Emporium in MK ... I think they were about $6 each. If I remember correctly they held 36 smooshed pennies and 6 smooshed quarters.
The total cost was $31.86:
$6.00 holder
$18.36 36 pennies @ 51¢ each
$7.50 6 quarters @ $1.25 each
Wm and Cissy loved searching for the penny presses, choosing which penny(ies) they wanted/needed and then pressing the pennies. And nearly a year later they love pulling out their holders and looking at the pennies. They are looking forward to collecting another batch this summer!