A Start for a 10 year old
I agree 100% with Minn. Btw, that's more or less what I did to get started as well. I bought gear over time, not all at once.
Getting one of the electrics now to bang around with and have some immediate fun with while building a kit is certainly not a bad idea. Many of them only use throttle and rudder for control, which is "different" from planes that have a seperate elevator control.