Real Spellers

The 4th grade team is working on a unit about immigration. My class has explored the word migrate and we decided –through lots of guidance- that the base is . We have talked about bound bases vs free bases. They seem to be getting the concept gradually.  

A question came up as Fiona and I were putting a lesson together where we peeled off the suffix <-ate> from base words. This was to help answer the question “is always a suffix and is it a suffix in the word ? When we were coming up with words to have the kids use, we discovered that almost all of the bases were bound bases. Do you know if there is a reason for this?  Are there other suffixes which are typically used only on bound bases? Due to time constraints, the kids and I aren’t going down this road but Fiona and I are curious.

Also, below is a matrix for the bound base . Would you please look at it and see if I got all the affixes down? It seems to work fine but I am still new at this so any input is appreciated!