diff --git a/examples/democoin/x/cool/keeper_test.go b/examples/democoin/x/cool/keeper_test.go
new file mode 100644
index 000000000..470efea0a
--- /dev/null
+++ b/examples/democoin/x/cool/keeper_test.go
@@ -0,0 +1,50 @@
+package cool
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	abci "github.com/tendermint/abci/types"
+	dbm "github.com/tendermint/tmlibs/db"
+
+	"github.com/cosmos/cosmos-sdk/store"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/wire"
+	auth "github.com/cosmos/cosmos-sdk/x/auth"
+	bank "github.com/cosmos/cosmos-sdk/x/bank"
+)
+
+func setupMultiStore() (sdk.MultiStore, *sdk.KVStoreKey) {
+	db := dbm.NewMemDB()
+	capKey := sdk.NewKVStoreKey("capkey")
+	ms := store.NewCommitMultiStore(db)
+	ms.MountStoreWithDB(capKey, sdk.StoreTypeIAVL, db)
+	ms.LoadLatestVersion()
+	return ms, capKey
+}
+
+func TestCoolKeeper(t *testing.T) {
+	ms, capKey := setupMultiStore()
+	cdc := wire.NewCodec()
+	auth.RegisterBaseAccount(cdc)
+
+	am := auth.NewAccountMapper(cdc, capKey, &auth.BaseAccount{})
+	ctx := sdk.NewContext(ms, abci.Header{}, false, nil)
+	ck := bank.NewKeeper(am)
+	keeper := NewKeeper(capKey, ck, DefaultCodespace)
+
+	err := keeper.InitGenesis(ctx, Genesis{"icy"})
+	assert.Nil(t, err)
+
+	genesis := keeper.WriteGenesis(ctx)
+	assert.Nil(t, err)
+	assert.Equal(t, genesis, Genesis{"icy"})
+
+	res := keeper.GetTrend(ctx)
+	assert.Equal(t, res, "icy")
+
+	keeper.setTrend(ctx, "fiery")
+	res = keeper.GetTrend(ctx)
+	assert.Equal(t, res, "fiery")
+}