Addendum
Building a cheap computer could be the first thing which comes to the mind of a technically inclined person. But efforts regarding this have been underway for for several decades without widespread success in getting access to mobile computing to the underprivileged from One Laptop Per Child to Raspberry Pi.
I've seen regular laptops with poor build quality being supplied to high school/college students(before COVID-19 pandemic), such devices won't survive handling by younger children and are an over-kill for their needs.
Besides, smartphones have proved themselves as the preferred mobile commuting device(from adoption rate) and cost lesser than any of the above full fledged computers for children.
Perhaps donating smartphones, computers at the scale of how we donate clothes, food items during other natural disasters could help alleviate this problem for some. But, then again phones and computers don't get replaced often in emerging economies; When they get replaced, the old often goes to someone who needs it within their family.
Without solving for electricity, Internet a solution in this direction could just be a part of overall solution.