I like the AE tuition books, have a look , maybe start on one he can cope with (8/9?) and then having boosted his confidence try the higher one.
is excellent, get a few wrong on purpose, then start playing in earnest..every right answer wins grains of rice for less fortunate children.
when reading , get him to write down any unfamilar words and look them up. Make a list of words and their definitions. Play 'pairs' games, can you turn up teh word and its definition.
You can also use a snakes and ladders board.
make or print out cards with target words (maybe with definitions on back?)and put in a pile
play snakes and ladders in the usual way. except when he gets to the bottom of a ladder he can only go up if he can answer a question from the pile ( give a definition, he has to give a word or vice versa), on a snake's head he can avoid going down if he can answer.
On your turn, he can prevent you going up a ladder by answering a question correctly. Similarly if you are on a snake's head , he has to answe r a question corectly so that you go down. Ifincorrect you stay where you are.
I love this game, many games are one sided if the adult is more knowledgeable. The temptation is to cheat and let them win (or be ruthless!). This wat the child controls teh game by theor knowledge ..and competetiveness wins out over reluctance to learn.
You can use all sorts of things for the question pack...
tables, spellings, equivalent fractions.........