given the following code:

import json 
foo = '{"root":"cfb-score","children":{"gamecode":{"attribute":"global-id"},"gamestate":{"attribute":"status-id","attribute":"status","attribute":"quarter","attribute":"minutes","attribute":"seconds","attribute":"team-possession-id","attribute":"yards-from-goal","attribute":"down","attribute":"distance","attribute":"segment-number","attribute":"active-state"},"gametype":{"attribute":"type","attribute":"detail"},"stadium":{"attribute":"name","attribute":"city","attribute":"state"},"visiting-team:team-name":{"attribute":"alias"},"visiting-team:team-code":{"attribute":"global-id"},"visiting-team:team-rank":{"attribute":"rank"}}}'bar = json.loads(foo)
print json.dumps(bar)

all the lowest level 'children' are truncated (or maybe more likely overwritten) except the last when using json.loads or json.load. Why? the json is well formed and can be validated here: http://json.parser.online.fr/

a chunk of the input:

"children" : {"gamecode" : {"attribute" :  "global-id"},"gamestate" : {"attribute" : "status-id", "attribute" : "status", "attribute" : "quarter", "attribute" : "minutes", "attribute" : "seconds", "attribute" : "team-possession-id", "attribute" : "yards-from-goal", "attribute" : "down", "attribute" : "distance", "attribute" : "segment-number", "attribute" : "active-state" }, 

turns to this chunk of output:

"children" : {"gamecode" : {"attribute" :  "global-id"},"gamestate" : {"attribute" : "active-state" }, 

The JSON is well-formed (i.e., syntactically valid) but semantically invalid. You can't have multiple keys with the same value in a Python dict, nor in a JS object. If you validate that input at the page you linked to, you'll see that the "JS eval" pane also shows the "truncated" data.

If you want multiple values, change the format of your data to have one key with an array value:

"gamestate" : {"attributes": ["status-id", "status", "quarter", ...]}, 

(Or, depending on what the overall data is like, you could just have the gamestate key directly link to an array instead of having another layer of nesting under the attribute key.)