We found EPGY very unsuitable for a five year old, I wouldn't expect it would be great for an even younger child.
ITA with the fun manipulative suggestions. In addition Grid perplexors might be fun, and the Flashkids ...for the gifted child workbooks in B&N are fun even to a relatively high level. I have not tried Beast Academy, but I've heard good things. Life of Fred books might be a fun read aloud.
In general I would expect that if your child is like mine you'll be doing a crash course in pedagogy to try and make things age appropriate.
